epoger@google.com | ec3ed6a | 2011-07-28 14:26:00 +0000 | [diff] [blame] | 1 | |
| 2 | /* |
| 3 | * Copyright 2006 The Android Open Source Project |
| 4 | * |
| 5 | * Use of this source code is governed by a BSD-style license that can be |
| 6 | * found in the LICENSE file. |
| 7 | */ |
| 8 | |
reed@android.com | 8a1c16f | 2008-12-17 15:59:43 +0000 | [diff] [blame] | 9 | |
| 10 | #include "SkBlurMask.h" |
tomhudson@google.com | 889bd8b | 2011-09-27 17:38:17 +0000 | [diff] [blame] | 11 | #include "SkMath.h" |
reed@android.com | 8a1c16f | 2008-12-17 15:59:43 +0000 | [diff] [blame] | 12 | #include "SkTemplates.h" |
tomhudson@google.com | 01224d5 | 2011-11-28 18:22:01 +0000 | [diff] [blame] | 13 | #include "SkEndian.h" |
| 14 | |
robertphillips@google.com | 7ce661d | 2013-08-27 16:14:03 +0000 | [diff] [blame] | 15 | |
reed@google.com | daaafa6 | 2014-04-29 15:20:16 +0000 | [diff] [blame] | 16 | // This constant approximates the scaling done in the software path's |
| 17 | // "high quality" mode, in SkBlurMask::Blur() (1 / sqrt(3)). |
| 18 | // IMHO, it actually should be 1: we blur "less" than we should do |
| 19 | // according to the CSS and canvas specs, simply because Safari does the same. |
| 20 | // Firefox used to do the same too, until 4.0 where they fixed it. So at some |
| 21 | // point we should probably get rid of these scaling constants and rebaseline |
| 22 | // all the blur tests. |
| 23 | static const SkScalar kBLUR_SIGMA_SCALE = 0.57735f; |
robertphillips@google.com | 7ce661d | 2013-08-27 16:14:03 +0000 | [diff] [blame] | 24 | |
reed@google.com | daaafa6 | 2014-04-29 15:20:16 +0000 | [diff] [blame] | 25 | SkScalar SkBlurMask::ConvertRadiusToSigma(SkScalar radius) { |
| 26 | return radius > 0 ? kBLUR_SIGMA_SCALE * radius + 0.5f : 0.0f; |
| 27 | } |
| 28 | |
| 29 | SkScalar SkBlurMask::ConvertSigmaToRadius(SkScalar sigma) { |
| 30 | return sigma > 0.5f ? (sigma - 0.5f) / kBLUR_SIGMA_SCALE : 0.0f; |
robertphillips@google.com | 7ce661d | 2013-08-27 16:14:03 +0000 | [diff] [blame] | 31 | } |
humper@google.com | 7c7292c | 2013-01-04 20:29:03 +0000 | [diff] [blame] | 32 | |
senorblanco@chromium.org | 9b0d4d7 | 2012-11-27 22:57:41 +0000 | [diff] [blame] | 33 | #define UNROLL_SEPARABLE_LOOPS |
| 34 | |
senorblanco@chromium.org | 908276b | 2012-11-15 20:27:35 +0000 | [diff] [blame] | 35 | /** |
| 36 | * This function performs a box blur in X, of the given radius. If the |
skia.committer@gmail.com | 884e60b | 2012-11-16 02:01:17 +0000 | [diff] [blame] | 37 | * "transpose" parameter is true, it will transpose the pixels on write, |
senorblanco@chromium.org | 908276b | 2012-11-15 20:27:35 +0000 | [diff] [blame] | 38 | * such that X and Y are swapped. Reads are always performed from contiguous |
| 39 | * memory in X, for speed. The destination buffer (dst) must be at least |
senorblanco@chromium.org | 9b0d4d7 | 2012-11-27 22:57:41 +0000 | [diff] [blame] | 40 | * (width + leftRadius + rightRadius) * height bytes in size. |
senorblanco@chromium.org | 4a525d7 | 2013-02-19 16:09:10 +0000 | [diff] [blame] | 41 | * |
| 42 | * This is what the inner loop looks like before unrolling, and with the two |
| 43 | * cases broken out separately (width < diameter, width >= diameter): |
skia.committer@gmail.com | 76bf70d | 2013-02-20 07:02:30 +0000 | [diff] [blame] | 44 | * |
senorblanco@chromium.org | 4a525d7 | 2013-02-19 16:09:10 +0000 | [diff] [blame] | 45 | * if (width < diameter) { |
| 46 | * for (int x = 0; x < width; ++x) { |
| 47 | * sum += *right++; |
skia.committer@gmail.com | 76bf70d | 2013-02-20 07:02:30 +0000 | [diff] [blame] | 48 | * *dptr = (sum * scale + half) >> 24; |
senorblanco@chromium.org | 4a525d7 | 2013-02-19 16:09:10 +0000 | [diff] [blame] | 49 | * dptr += dst_x_stride; |
| 50 | * } |
| 51 | * for (int x = width; x < diameter; ++x) { |
| 52 | * *dptr = (sum * scale + half) >> 24; |
| 53 | * dptr += dst_x_stride; |
| 54 | * } |
| 55 | * for (int x = 0; x < width; ++x) { |
| 56 | * *dptr = (sum * scale + half) >> 24; |
| 57 | * sum -= *left++; |
| 58 | * dptr += dst_x_stride; |
| 59 | * } |
| 60 | * } else { |
| 61 | * for (int x = 0; x < diameter; ++x) { |
| 62 | * sum += *right++; |
| 63 | * *dptr = (sum * scale + half) >> 24; |
| 64 | * dptr += dst_x_stride; |
| 65 | * } |
| 66 | * for (int x = diameter; x < width; ++x) { |
| 67 | * sum += *right++; |
| 68 | * *dptr = (sum * scale + half) >> 24; |
| 69 | * sum -= *left++; |
| 70 | * dptr += dst_x_stride; |
| 71 | * } |
| 72 | * for (int x = 0; x < diameter; ++x) { |
| 73 | * *dptr = (sum * scale + half) >> 24; |
| 74 | * sum -= *left++; |
| 75 | * dptr += dst_x_stride; |
| 76 | * } |
| 77 | * } |
senorblanco@chromium.org | 908276b | 2012-11-15 20:27:35 +0000 | [diff] [blame] | 78 | */ |
| 79 | static int boxBlur(const uint8_t* src, int src_y_stride, uint8_t* dst, |
senorblanco@chromium.org | c438130 | 2012-11-16 17:22:33 +0000 | [diff] [blame] | 80 | int leftRadius, int rightRadius, int width, int height, |
| 81 | bool transpose) |
senorblanco@chromium.org | 71f0f34 | 2012-11-13 20:35:21 +0000 | [diff] [blame] | 82 | { |
senorblanco@chromium.org | 9b0d4d7 | 2012-11-27 22:57:41 +0000 | [diff] [blame] | 83 | int diameter = leftRadius + rightRadius; |
| 84 | int kernelSize = diameter + 1; |
| 85 | int border = SkMin32(width, diameter); |
senorblanco@chromium.org | 71f0f34 | 2012-11-13 20:35:21 +0000 | [diff] [blame] | 86 | uint32_t scale = (1 << 24) / kernelSize; |
senorblanco@chromium.org | c438130 | 2012-11-16 17:22:33 +0000 | [diff] [blame] | 87 | int new_width = width + SkMax32(leftRadius, rightRadius) * 2; |
senorblanco@chromium.org | 908276b | 2012-11-15 20:27:35 +0000 | [diff] [blame] | 88 | int dst_x_stride = transpose ? height : 1; |
| 89 | int dst_y_stride = transpose ? 1 : new_width; |
senorblanco@chromium.org | 4a525d7 | 2013-02-19 16:09:10 +0000 | [diff] [blame] | 90 | uint32_t half = 1 << 23; |
senorblanco@chromium.org | 71f0f34 | 2012-11-13 20:35:21 +0000 | [diff] [blame] | 91 | for (int y = 0; y < height; ++y) { |
senorblanco@chromium.org | 4a525d7 | 2013-02-19 16:09:10 +0000 | [diff] [blame] | 92 | uint32_t sum = 0; |
senorblanco@chromium.org | 908276b | 2012-11-15 20:27:35 +0000 | [diff] [blame] | 93 | uint8_t* dptr = dst + y * dst_y_stride; |
| 94 | const uint8_t* right = src + y * src_y_stride; |
| 95 | const uint8_t* left = right; |
senorblanco@chromium.org | 336b4da | 2012-11-20 17:09:40 +0000 | [diff] [blame] | 96 | for (int x = 0; x < rightRadius - leftRadius; x++) { |
| 97 | *dptr = 0; |
| 98 | dptr += dst_x_stride; |
senorblanco@chromium.org | c438130 | 2012-11-16 17:22:33 +0000 | [diff] [blame] | 99 | } |
senorblanco@chromium.org | 9b0d4d7 | 2012-11-27 22:57:41 +0000 | [diff] [blame] | 100 | #define LEFT_BORDER_ITER \ |
| 101 | sum += *right++; \ |
senorblanco@chromium.org | 4a525d7 | 2013-02-19 16:09:10 +0000 | [diff] [blame] | 102 | *dptr = (sum * scale + half) >> 24; \ |
senorblanco@chromium.org | 908276b | 2012-11-15 20:27:35 +0000 | [diff] [blame] | 103 | dptr += dst_x_stride; |
senorblanco@chromium.org | 9b0d4d7 | 2012-11-27 22:57:41 +0000 | [diff] [blame] | 104 | |
| 105 | int x = 0; |
| 106 | #ifdef UNROLL_SEPARABLE_LOOPS |
| 107 | for (; x < border - 16; x += 16) { |
| 108 | LEFT_BORDER_ITER |
| 109 | LEFT_BORDER_ITER |
| 110 | LEFT_BORDER_ITER |
| 111 | LEFT_BORDER_ITER |
| 112 | LEFT_BORDER_ITER |
| 113 | LEFT_BORDER_ITER |
| 114 | LEFT_BORDER_ITER |
| 115 | LEFT_BORDER_ITER |
| 116 | LEFT_BORDER_ITER |
| 117 | LEFT_BORDER_ITER |
| 118 | LEFT_BORDER_ITER |
| 119 | LEFT_BORDER_ITER |
| 120 | LEFT_BORDER_ITER |
| 121 | LEFT_BORDER_ITER |
| 122 | LEFT_BORDER_ITER |
| 123 | LEFT_BORDER_ITER |
senorblanco@chromium.org | 71f0f34 | 2012-11-13 20:35:21 +0000 | [diff] [blame] | 124 | } |
senorblanco@chromium.org | 9b0d4d7 | 2012-11-27 22:57:41 +0000 | [diff] [blame] | 125 | #endif |
| 126 | for (; x < border; ++x) { |
| 127 | LEFT_BORDER_ITER |
| 128 | } |
| 129 | #undef LEFT_BORDER_ITER |
| 130 | #define TRIVIAL_ITER \ |
senorblanco@chromium.org | 4a525d7 | 2013-02-19 16:09:10 +0000 | [diff] [blame] | 131 | *dptr = (sum * scale + half) >> 24; \ |
senorblanco@chromium.org | 908276b | 2012-11-15 20:27:35 +0000 | [diff] [blame] | 132 | dptr += dst_x_stride; |
senorblanco@chromium.org | 9b0d4d7 | 2012-11-27 22:57:41 +0000 | [diff] [blame] | 133 | x = width; |
| 134 | #ifdef UNROLL_SEPARABLE_LOOPS |
| 135 | for (; x < diameter - 16; x += 16) { |
| 136 | TRIVIAL_ITER |
| 137 | TRIVIAL_ITER |
| 138 | TRIVIAL_ITER |
| 139 | TRIVIAL_ITER |
| 140 | TRIVIAL_ITER |
| 141 | TRIVIAL_ITER |
| 142 | TRIVIAL_ITER |
| 143 | TRIVIAL_ITER |
| 144 | TRIVIAL_ITER |
| 145 | TRIVIAL_ITER |
| 146 | TRIVIAL_ITER |
| 147 | TRIVIAL_ITER |
| 148 | TRIVIAL_ITER |
| 149 | TRIVIAL_ITER |
| 150 | TRIVIAL_ITER |
| 151 | TRIVIAL_ITER |
senorblanco@chromium.org | 71f0f34 | 2012-11-13 20:35:21 +0000 | [diff] [blame] | 152 | } |
senorblanco@chromium.org | 9b0d4d7 | 2012-11-27 22:57:41 +0000 | [diff] [blame] | 153 | #endif |
| 154 | for (; x < diameter; ++x) { |
| 155 | TRIVIAL_ITER |
| 156 | } |
| 157 | #undef TRIVIAL_ITER |
| 158 | #define CENTER_ITER \ |
| 159 | sum += *right++; \ |
senorblanco@chromium.org | 4a525d7 | 2013-02-19 16:09:10 +0000 | [diff] [blame] | 160 | *dptr = (sum * scale + half) >> 24; \ |
senorblanco@chromium.org | 9b0d4d7 | 2012-11-27 22:57:41 +0000 | [diff] [blame] | 161 | sum -= *left++; \ |
senorblanco@chromium.org | 908276b | 2012-11-15 20:27:35 +0000 | [diff] [blame] | 162 | dptr += dst_x_stride; |
senorblanco@chromium.org | 9b0d4d7 | 2012-11-27 22:57:41 +0000 | [diff] [blame] | 163 | |
| 164 | x = diameter; |
| 165 | #ifdef UNROLL_SEPARABLE_LOOPS |
| 166 | for (; x < width - 16; x += 16) { |
| 167 | CENTER_ITER |
| 168 | CENTER_ITER |
| 169 | CENTER_ITER |
| 170 | CENTER_ITER |
| 171 | CENTER_ITER |
| 172 | CENTER_ITER |
| 173 | CENTER_ITER |
| 174 | CENTER_ITER |
| 175 | CENTER_ITER |
| 176 | CENTER_ITER |
| 177 | CENTER_ITER |
| 178 | CENTER_ITER |
| 179 | CENTER_ITER |
| 180 | CENTER_ITER |
| 181 | CENTER_ITER |
| 182 | CENTER_ITER |
senorblanco@chromium.org | 71f0f34 | 2012-11-13 20:35:21 +0000 | [diff] [blame] | 183 | } |
senorblanco@chromium.org | 9b0d4d7 | 2012-11-27 22:57:41 +0000 | [diff] [blame] | 184 | #endif |
| 185 | for (; x < width; ++x) { |
| 186 | CENTER_ITER |
| 187 | } |
| 188 | #undef CENTER_ITER |
| 189 | #define RIGHT_BORDER_ITER \ |
senorblanco@chromium.org | 4a525d7 | 2013-02-19 16:09:10 +0000 | [diff] [blame] | 190 | *dptr = (sum * scale + half) >> 24; \ |
senorblanco@chromium.org | 9b0d4d7 | 2012-11-27 22:57:41 +0000 | [diff] [blame] | 191 | sum -= *left++; \ |
senorblanco@chromium.org | 908276b | 2012-11-15 20:27:35 +0000 | [diff] [blame] | 192 | dptr += dst_x_stride; |
senorblanco@chromium.org | 9b0d4d7 | 2012-11-27 22:57:41 +0000 | [diff] [blame] | 193 | |
| 194 | x = 0; |
| 195 | #ifdef UNROLL_SEPARABLE_LOOPS |
| 196 | for (; x < border - 16; x += 16) { |
| 197 | RIGHT_BORDER_ITER |
| 198 | RIGHT_BORDER_ITER |
| 199 | RIGHT_BORDER_ITER |
| 200 | RIGHT_BORDER_ITER |
| 201 | RIGHT_BORDER_ITER |
| 202 | RIGHT_BORDER_ITER |
| 203 | RIGHT_BORDER_ITER |
| 204 | RIGHT_BORDER_ITER |
| 205 | RIGHT_BORDER_ITER |
| 206 | RIGHT_BORDER_ITER |
| 207 | RIGHT_BORDER_ITER |
| 208 | RIGHT_BORDER_ITER |
| 209 | RIGHT_BORDER_ITER |
| 210 | RIGHT_BORDER_ITER |
| 211 | RIGHT_BORDER_ITER |
| 212 | RIGHT_BORDER_ITER |
senorblanco@chromium.org | 71f0f34 | 2012-11-13 20:35:21 +0000 | [diff] [blame] | 213 | } |
senorblanco@chromium.org | 9b0d4d7 | 2012-11-27 22:57:41 +0000 | [diff] [blame] | 214 | #endif |
| 215 | for (; x < border; ++x) { |
| 216 | RIGHT_BORDER_ITER |
| 217 | } |
| 218 | #undef RIGHT_BORDER_ITER |
humper@google.com | a99a92c | 2013-02-20 16:42:06 +0000 | [diff] [blame] | 219 | for (int x = 0; x < leftRadius - rightRadius; ++x) { |
senorblanco@chromium.org | 336b4da | 2012-11-20 17:09:40 +0000 | [diff] [blame] | 220 | *dptr = 0; |
| 221 | dptr += dst_x_stride; |
senorblanco@chromium.org | c438130 | 2012-11-16 17:22:33 +0000 | [diff] [blame] | 222 | } |
senorblanco@chromium.org | 71f0f34 | 2012-11-13 20:35:21 +0000 | [diff] [blame] | 223 | SkASSERT(sum == 0); |
| 224 | } |
senorblanco@chromium.org | 908276b | 2012-11-15 20:27:35 +0000 | [diff] [blame] | 225 | return new_width; |
senorblanco@chromium.org | 71f0f34 | 2012-11-13 20:35:21 +0000 | [diff] [blame] | 226 | } |
| 227 | |
senorblanco@chromium.org | 9b0d4d7 | 2012-11-27 22:57:41 +0000 | [diff] [blame] | 228 | /** |
| 229 | * This variant of the box blur handles blurring of non-integer radii. It |
| 230 | * keeps two running sums: an outer sum for the rounded-up kernel radius, and |
| 231 | * an inner sum for the rounded-down kernel radius. For each pixel, it linearly |
| 232 | * interpolates between them. In float this would be: |
| 233 | * outer_weight * outer_sum / kernelSize + |
| 234 | * (1.0 - outer_weight) * innerSum / (kernelSize - 2) |
skia.committer@gmail.com | 76bf70d | 2013-02-20 07:02:30 +0000 | [diff] [blame] | 235 | * |
senorblanco@chromium.org | 4a525d7 | 2013-02-19 16:09:10 +0000 | [diff] [blame] | 236 | * This is what the inner loop looks like before unrolling, and with the two |
| 237 | * cases broken out separately (width < diameter, width >= diameter): |
skia.committer@gmail.com | 76bf70d | 2013-02-20 07:02:30 +0000 | [diff] [blame] | 238 | * |
senorblanco@chromium.org | 4a525d7 | 2013-02-19 16:09:10 +0000 | [diff] [blame] | 239 | * if (width < diameter) { |
| 240 | * for (int x = 0; x < width; x++) { |
| 241 | * inner_sum = outer_sum; |
| 242 | * outer_sum += *right++; |
| 243 | * *dptr = (outer_sum * outer_scale + inner_sum * inner_scale + half) >> 24; |
| 244 | * dptr += dst_x_stride; |
| 245 | * } |
| 246 | * for (int x = width; x < diameter; ++x) { |
| 247 | * *dptr = (outer_sum * outer_scale + inner_sum * inner_scale + half) >> 24; |
| 248 | * dptr += dst_x_stride; |
| 249 | * } |
| 250 | * for (int x = 0; x < width; x++) { |
| 251 | * inner_sum = outer_sum - *left++; |
| 252 | * *dptr = (outer_sum * outer_scale + inner_sum * inner_scale + half) >> 24; |
| 253 | * dptr += dst_x_stride; |
| 254 | * outer_sum = inner_sum; |
| 255 | * } |
| 256 | * } else { |
| 257 | * for (int x = 0; x < diameter; x++) { |
| 258 | * inner_sum = outer_sum; |
| 259 | * outer_sum += *right++; |
| 260 | * *dptr = (outer_sum * outer_scale + inner_sum * inner_scale + half) >> 24; |
| 261 | * dptr += dst_x_stride; |
| 262 | * } |
| 263 | * for (int x = diameter; x < width; ++x) { |
| 264 | * inner_sum = outer_sum - *left; |
| 265 | * outer_sum += *right++; |
| 266 | * *dptr = (outer_sum * outer_scale + inner_sum * inner_scale + half) >> 24; |
| 267 | * dptr += dst_x_stride; |
| 268 | * outer_sum -= *left++; |
| 269 | * } |
| 270 | * for (int x = 0; x < diameter; x++) { |
| 271 | * inner_sum = outer_sum - *left++; |
| 272 | * *dptr = (outer_sum * outer_scale + inner_sum * inner_scale + half) >> 24; |
| 273 | * dptr += dst_x_stride; |
| 274 | * outer_sum = inner_sum; |
| 275 | * } |
| 276 | * } |
| 277 | * } |
| 278 | * return new_width; |
senorblanco@chromium.org | 9b0d4d7 | 2012-11-27 22:57:41 +0000 | [diff] [blame] | 279 | */ |
senorblanco@chromium.org | 4a525d7 | 2013-02-19 16:09:10 +0000 | [diff] [blame] | 280 | |
senorblanco@chromium.org | 9b0d4d7 | 2012-11-27 22:57:41 +0000 | [diff] [blame] | 281 | static int boxBlurInterp(const uint8_t* src, int src_y_stride, uint8_t* dst, |
| 282 | int radius, int width, int height, |
| 283 | bool transpose, uint8_t outer_weight) |
| 284 | { |
| 285 | int diameter = radius * 2; |
| 286 | int kernelSize = diameter + 1; |
| 287 | int border = SkMin32(width, diameter); |
| 288 | int inner_weight = 255 - outer_weight; |
| 289 | outer_weight += outer_weight >> 7; |
| 290 | inner_weight += inner_weight >> 7; |
| 291 | uint32_t outer_scale = (outer_weight << 16) / kernelSize; |
| 292 | uint32_t inner_scale = (inner_weight << 16) / (kernelSize - 2); |
senorblanco@chromium.org | 4a525d7 | 2013-02-19 16:09:10 +0000 | [diff] [blame] | 293 | uint32_t half = 1 << 23; |
senorblanco@chromium.org | 9b0d4d7 | 2012-11-27 22:57:41 +0000 | [diff] [blame] | 294 | int new_width = width + diameter; |
| 295 | int dst_x_stride = transpose ? height : 1; |
| 296 | int dst_y_stride = transpose ? 1 : new_width; |
| 297 | for (int y = 0; y < height; ++y) { |
senorblanco@chromium.org | 4a525d7 | 2013-02-19 16:09:10 +0000 | [diff] [blame] | 298 | uint32_t outer_sum = 0, inner_sum = 0; |
senorblanco@chromium.org | 9b0d4d7 | 2012-11-27 22:57:41 +0000 | [diff] [blame] | 299 | uint8_t* dptr = dst + y * dst_y_stride; |
| 300 | const uint8_t* right = src + y * src_y_stride; |
| 301 | const uint8_t* left = right; |
| 302 | int x = 0; |
| 303 | |
| 304 | #define LEFT_BORDER_ITER \ |
| 305 | inner_sum = outer_sum; \ |
| 306 | outer_sum += *right++; \ |
senorblanco@chromium.org | 4a525d7 | 2013-02-19 16:09:10 +0000 | [diff] [blame] | 307 | *dptr = (outer_sum * outer_scale + inner_sum * inner_scale + half) >> 24; \ |
senorblanco@chromium.org | 9b0d4d7 | 2012-11-27 22:57:41 +0000 | [diff] [blame] | 308 | dptr += dst_x_stride; |
| 309 | |
| 310 | #ifdef UNROLL_SEPARABLE_LOOPS |
| 311 | for (;x < border - 16; x += 16) { |
| 312 | LEFT_BORDER_ITER |
| 313 | LEFT_BORDER_ITER |
| 314 | LEFT_BORDER_ITER |
| 315 | LEFT_BORDER_ITER |
| 316 | LEFT_BORDER_ITER |
| 317 | LEFT_BORDER_ITER |
| 318 | LEFT_BORDER_ITER |
| 319 | LEFT_BORDER_ITER |
| 320 | LEFT_BORDER_ITER |
| 321 | LEFT_BORDER_ITER |
| 322 | LEFT_BORDER_ITER |
| 323 | LEFT_BORDER_ITER |
| 324 | LEFT_BORDER_ITER |
| 325 | LEFT_BORDER_ITER |
| 326 | LEFT_BORDER_ITER |
| 327 | LEFT_BORDER_ITER |
| 328 | } |
| 329 | #endif |
| 330 | |
humper@google.com | a99a92c | 2013-02-20 16:42:06 +0000 | [diff] [blame] | 331 | for (;x < border; ++x) { |
senorblanco@chromium.org | 9b0d4d7 | 2012-11-27 22:57:41 +0000 | [diff] [blame] | 332 | LEFT_BORDER_ITER |
| 333 | } |
| 334 | #undef LEFT_BORDER_ITER |
| 335 | for (int x = width; x < diameter; ++x) { |
senorblanco@chromium.org | 4a525d7 | 2013-02-19 16:09:10 +0000 | [diff] [blame] | 336 | *dptr = (outer_sum * outer_scale + inner_sum * inner_scale + half) >> 24; |
senorblanco@chromium.org | 9b0d4d7 | 2012-11-27 22:57:41 +0000 | [diff] [blame] | 337 | dptr += dst_x_stride; |
| 338 | } |
| 339 | x = diameter; |
| 340 | |
| 341 | #define CENTER_ITER \ |
| 342 | inner_sum = outer_sum - *left; \ |
| 343 | outer_sum += *right++; \ |
senorblanco@chromium.org | 4a525d7 | 2013-02-19 16:09:10 +0000 | [diff] [blame] | 344 | *dptr = (outer_sum * outer_scale + inner_sum * inner_scale + half) >> 24; \ |
senorblanco@chromium.org | 9b0d4d7 | 2012-11-27 22:57:41 +0000 | [diff] [blame] | 345 | dptr += dst_x_stride; \ |
| 346 | outer_sum -= *left++; |
| 347 | |
| 348 | #ifdef UNROLL_SEPARABLE_LOOPS |
| 349 | for (; x < width - 16; x += 16) { |
| 350 | CENTER_ITER |
| 351 | CENTER_ITER |
| 352 | CENTER_ITER |
| 353 | CENTER_ITER |
| 354 | CENTER_ITER |
| 355 | CENTER_ITER |
| 356 | CENTER_ITER |
| 357 | CENTER_ITER |
| 358 | CENTER_ITER |
| 359 | CENTER_ITER |
| 360 | CENTER_ITER |
| 361 | CENTER_ITER |
| 362 | CENTER_ITER |
| 363 | CENTER_ITER |
| 364 | CENTER_ITER |
| 365 | CENTER_ITER |
| 366 | } |
| 367 | #endif |
| 368 | for (; x < width; ++x) { |
| 369 | CENTER_ITER |
| 370 | } |
| 371 | #undef CENTER_ITER |
| 372 | |
| 373 | #define RIGHT_BORDER_ITER \ |
| 374 | inner_sum = outer_sum - *left++; \ |
senorblanco@chromium.org | 4a525d7 | 2013-02-19 16:09:10 +0000 | [diff] [blame] | 375 | *dptr = (outer_sum * outer_scale + inner_sum * inner_scale + half) >> 24; \ |
senorblanco@chromium.org | 9b0d4d7 | 2012-11-27 22:57:41 +0000 | [diff] [blame] | 376 | dptr += dst_x_stride; \ |
| 377 | outer_sum = inner_sum; |
| 378 | |
| 379 | x = 0; |
| 380 | #ifdef UNROLL_SEPARABLE_LOOPS |
| 381 | for (; x < border - 16; x += 16) { |
| 382 | RIGHT_BORDER_ITER |
| 383 | RIGHT_BORDER_ITER |
| 384 | RIGHT_BORDER_ITER |
| 385 | RIGHT_BORDER_ITER |
| 386 | RIGHT_BORDER_ITER |
| 387 | RIGHT_BORDER_ITER |
| 388 | RIGHT_BORDER_ITER |
| 389 | RIGHT_BORDER_ITER |
| 390 | RIGHT_BORDER_ITER |
| 391 | RIGHT_BORDER_ITER |
| 392 | RIGHT_BORDER_ITER |
| 393 | RIGHT_BORDER_ITER |
| 394 | RIGHT_BORDER_ITER |
| 395 | RIGHT_BORDER_ITER |
| 396 | RIGHT_BORDER_ITER |
| 397 | RIGHT_BORDER_ITER |
| 398 | } |
| 399 | #endif |
humper@google.com | a99a92c | 2013-02-20 16:42:06 +0000 | [diff] [blame] | 400 | for (; x < border; ++x) { |
senorblanco@chromium.org | 9b0d4d7 | 2012-11-27 22:57:41 +0000 | [diff] [blame] | 401 | RIGHT_BORDER_ITER |
| 402 | } |
| 403 | #undef RIGHT_BORDER_ITER |
| 404 | SkASSERT(outer_sum == 0 && inner_sum == 0); |
| 405 | } |
| 406 | return new_width; |
| 407 | } |
| 408 | |
senorblanco@chromium.org | c438130 | 2012-11-16 17:22:33 +0000 | [diff] [blame] | 409 | static void get_adjusted_radii(SkScalar passRadius, int *loRadius, int *hiRadius) |
| 410 | { |
reed@google.com | e1ca705 | 2013-12-17 19:22:07 +0000 | [diff] [blame] | 411 | *loRadius = *hiRadius = SkScalarCeilToInt(passRadius); |
commit-bot@chromium.org | 4b413c8 | 2013-11-25 19:44:07 +0000 | [diff] [blame] | 412 | if (SkIntToScalar(*hiRadius) - passRadius > 0.5f) { |
senorblanco@chromium.org | c438130 | 2012-11-16 17:22:33 +0000 | [diff] [blame] | 413 | *loRadius = *hiRadius - 1; |
| 414 | } |
| 415 | } |
| 416 | |
reed@android.com | 8a1c16f | 2008-12-17 15:59:43 +0000 | [diff] [blame] | 417 | #include "SkColorPriv.h" |
| 418 | |
reed@android.com | 0e3c664 | 2009-09-18 13:41:56 +0000 | [diff] [blame] | 419 | static void merge_src_with_blur(uint8_t dst[], int dstRB, |
| 420 | const uint8_t src[], int srcRB, |
| 421 | const uint8_t blur[], int blurRB, |
| 422 | int sw, int sh) { |
| 423 | dstRB -= sw; |
| 424 | srcRB -= sw; |
| 425 | blurRB -= sw; |
| 426 | while (--sh >= 0) { |
| 427 | for (int x = sw - 1; x >= 0; --x) { |
reed@android.com | 8a1c16f | 2008-12-17 15:59:43 +0000 | [diff] [blame] | 428 | *dst = SkToU8(SkAlphaMul(*blur, SkAlpha255To256(*src))); |
| 429 | dst += 1; |
| 430 | src += 1; |
| 431 | blur += 1; |
| 432 | } |
reed@android.com | 0e3c664 | 2009-09-18 13:41:56 +0000 | [diff] [blame] | 433 | dst += dstRB; |
| 434 | src += srcRB; |
| 435 | blur += blurRB; |
reed@android.com | 8a1c16f | 2008-12-17 15:59:43 +0000 | [diff] [blame] | 436 | } |
| 437 | } |
| 438 | |
| 439 | static void clamp_with_orig(uint8_t dst[], int dstRowBytes, |
reed@android.com | 0e3c664 | 2009-09-18 13:41:56 +0000 | [diff] [blame] | 440 | const uint8_t src[], int srcRowBytes, |
| 441 | int sw, int sh, |
commit-bot@chromium.org | e396455 | 2014-04-28 16:25:35 +0000 | [diff] [blame] | 442 | SkBlurStyle style) { |
reed@android.com | 8a1c16f | 2008-12-17 15:59:43 +0000 | [diff] [blame] | 443 | int x; |
reed@android.com | 0e3c664 | 2009-09-18 13:41:56 +0000 | [diff] [blame] | 444 | while (--sh >= 0) { |
reed@android.com | 8a1c16f | 2008-12-17 15:59:43 +0000 | [diff] [blame] | 445 | switch (style) { |
commit-bot@chromium.org | e396455 | 2014-04-28 16:25:35 +0000 | [diff] [blame] | 446 | case kSolid_SkBlurStyle: |
reed@android.com | 0e3c664 | 2009-09-18 13:41:56 +0000 | [diff] [blame] | 447 | for (x = sw - 1; x >= 0; --x) { |
| 448 | int s = *src; |
| 449 | int d = *dst; |
| 450 | *dst = SkToU8(s + d - SkMulDiv255Round(s, d)); |
reed@android.com | 8a1c16f | 2008-12-17 15:59:43 +0000 | [diff] [blame] | 451 | dst += 1; |
| 452 | src += 1; |
| 453 | } |
| 454 | break; |
commit-bot@chromium.org | e396455 | 2014-04-28 16:25:35 +0000 | [diff] [blame] | 455 | case kOuter_SkBlurStyle: |
reed@android.com | 0e3c664 | 2009-09-18 13:41:56 +0000 | [diff] [blame] | 456 | for (x = sw - 1; x >= 0; --x) { |
| 457 | if (*src) { |
reed@android.com | 8a1c16f | 2008-12-17 15:59:43 +0000 | [diff] [blame] | 458 | *dst = SkToU8(SkAlphaMul(*dst, SkAlpha255To256(255 - *src))); |
reed@android.com | 0e3c664 | 2009-09-18 13:41:56 +0000 | [diff] [blame] | 459 | } |
reed@android.com | 8a1c16f | 2008-12-17 15:59:43 +0000 | [diff] [blame] | 460 | dst += 1; |
| 461 | src += 1; |
| 462 | } |
| 463 | break; |
| 464 | default: |
tomhudson@google.com | 0c00f21 | 2011-12-28 14:59:50 +0000 | [diff] [blame] | 465 | SkDEBUGFAIL("Unexpected blur style here"); |
reed@android.com | 8a1c16f | 2008-12-17 15:59:43 +0000 | [diff] [blame] | 466 | break; |
| 467 | } |
| 468 | dst += dstRowBytes - sw; |
reed@android.com | 0e3c664 | 2009-09-18 13:41:56 +0000 | [diff] [blame] | 469 | src += srcRowBytes - sw; |
reed@android.com | 8a1c16f | 2008-12-17 15:59:43 +0000 | [diff] [blame] | 470 | } |
| 471 | } |
| 472 | |
reed@google.com | 03016a3 | 2011-08-12 14:59:59 +0000 | [diff] [blame] | 473 | /////////////////////////////////////////////////////////////////////////////// |
reed@android.com | 8a1c16f | 2008-12-17 15:59:43 +0000 | [diff] [blame] | 474 | |
bsalomon@google.com | 33cdbde | 2013-01-11 20:54:44 +0000 | [diff] [blame] | 475 | // we use a local function to wrap the class static method to work around |
reed@android.com | 8a1c16f | 2008-12-17 15:59:43 +0000 | [diff] [blame] | 476 | // a bug in gcc98 |
| 477 | void SkMask_FreeImage(uint8_t* image); |
reed@google.com | 03016a3 | 2011-08-12 14:59:59 +0000 | [diff] [blame] | 478 | void SkMask_FreeImage(uint8_t* image) { |
reed@android.com | 8a1c16f | 2008-12-17 15:59:43 +0000 | [diff] [blame] | 479 | SkMask::FreeImage(image); |
| 480 | } |
| 481 | |
commit-bot@chromium.org | 3d8bf23 | 2014-04-28 19:49:24 +0000 | [diff] [blame] | 482 | bool SkBlurMask::BoxBlur(SkMask* dst, const SkMask& src, |
| 483 | SkScalar sigma, SkBlurStyle style, SkBlurQuality quality, |
| 484 | SkIPoint* margin, bool force_quality) { |
| 485 | |
reed@google.com | 03016a3 | 2011-08-12 14:59:59 +0000 | [diff] [blame] | 486 | if (src.fFormat != SkMask::kA8_Format) { |
reed@android.com | 8a1c16f | 2008-12-17 15:59:43 +0000 | [diff] [blame] | 487 | return false; |
reed@google.com | 03016a3 | 2011-08-12 14:59:59 +0000 | [diff] [blame] | 488 | } |
reed@android.com | 8a1c16f | 2008-12-17 15:59:43 +0000 | [diff] [blame] | 489 | |
senorblanco@chromium.org | 4868e6b | 2011-02-18 19:03:01 +0000 | [diff] [blame] | 490 | // Force high quality off for small radii (performance) |
commit-bot@chromium.org | 3d8bf23 | 2014-04-28 19:49:24 +0000 | [diff] [blame] | 491 | if (!force_quality && sigma <= SkIntToScalar(2)) { |
commit-bot@chromium.org | e396455 | 2014-04-28 16:25:35 +0000 | [diff] [blame] | 492 | quality = kLow_SkBlurQuality; |
senorblanco@chromium.org | 91f489a | 2012-11-29 17:09:27 +0000 | [diff] [blame] | 493 | } |
skia.committer@gmail.com | d454ec1 | 2013-02-21 07:15:03 +0000 | [diff] [blame] | 494 | |
robertphillips@google.com | 7ce661d | 2013-08-27 16:14:03 +0000 | [diff] [blame] | 495 | SkScalar passRadius; |
commit-bot@chromium.org | e396455 | 2014-04-28 16:25:35 +0000 | [diff] [blame] | 496 | if (kHigh_SkBlurQuality == quality) { |
robertphillips@google.com | 7ce661d | 2013-08-27 16:14:03 +0000 | [diff] [blame] | 497 | // For the high quality path the 3 pass box blur kernel width is |
| 498 | // 6*rad+1 while the full Gaussian width is 6*sigma. |
| 499 | passRadius = sigma - (1/6.0f); |
| 500 | } else { |
skia.committer@gmail.com | 7bd141d | 2013-08-28 07:01:18 +0000 | [diff] [blame] | 501 | // For the low quality path we only attempt to cover 3*sigma of the |
| 502 | // Gaussian blur area (1.5*sigma on each side). The single pass box |
robertphillips@google.com | 7ce661d | 2013-08-27 16:14:03 +0000 | [diff] [blame] | 503 | // blur's kernel size is 2*rad+1. |
| 504 | passRadius = 1.5f*sigma - 0.5f; |
| 505 | } |
| 506 | |
skia.committer@gmail.com | d454ec1 | 2013-02-21 07:15:03 +0000 | [diff] [blame] | 507 | // highQuality: use three box blur passes as a cheap way |
humper@google.com | a99a92c | 2013-02-20 16:42:06 +0000 | [diff] [blame] | 508 | // to approximate a Gaussian blur |
commit-bot@chromium.org | e396455 | 2014-04-28 16:25:35 +0000 | [diff] [blame] | 509 | int passCount = (kHigh_SkBlurQuality == quality) ? 3 : 1; |
humper@google.com | a99a92c | 2013-02-20 16:42:06 +0000 | [diff] [blame] | 510 | |
reed@google.com | e1ca705 | 2013-12-17 19:22:07 +0000 | [diff] [blame] | 511 | int rx = SkScalarCeilToInt(passRadius); |
| 512 | int outerWeight = 255 - SkScalarRoundToInt((SkIntToScalar(rx) - passRadius) * 255); |
reed@android.com | 8a1c16f | 2008-12-17 15:59:43 +0000 | [diff] [blame] | 513 | |
| 514 | SkASSERT(rx >= 0); |
humper@google.com | a99a92c | 2013-02-20 16:42:06 +0000 | [diff] [blame] | 515 | SkASSERT((unsigned)outerWeight <= 255); |
reed@android.com | 0e3c664 | 2009-09-18 13:41:56 +0000 | [diff] [blame] | 516 | if (rx <= 0) { |
reed@android.com | 8a1c16f | 2008-12-17 15:59:43 +0000 | [diff] [blame] | 517 | return false; |
reed@android.com | 0e3c664 | 2009-09-18 13:41:56 +0000 | [diff] [blame] | 518 | } |
reed@android.com | 8a1c16f | 2008-12-17 15:59:43 +0000 | [diff] [blame] | 519 | |
| 520 | int ry = rx; // only do square blur for now |
| 521 | |
senorblanco@chromium.org | 4868e6b | 2011-02-18 19:03:01 +0000 | [diff] [blame] | 522 | int padx = passCount * rx; |
| 523 | int pady = passCount * ry; |
skia.committer@gmail.com | d454ec1 | 2013-02-21 07:15:03 +0000 | [diff] [blame] | 524 | |
bungeman@google.com | 5af16f8 | 2011-09-02 15:06:44 +0000 | [diff] [blame] | 525 | if (margin) { |
| 526 | margin->set(padx, pady); |
| 527 | } |
senorblanco@chromium.org | 4868e6b | 2011-02-18 19:03:01 +0000 | [diff] [blame] | 528 | dst->fBounds.set(src.fBounds.fLeft - padx, src.fBounds.fTop - pady, |
robertphillips@google.com | 7ce661d | 2013-08-27 16:14:03 +0000 | [diff] [blame] | 529 | src.fBounds.fRight + padx, src.fBounds.fBottom + pady); |
skia.committer@gmail.com | d454ec1 | 2013-02-21 07:15:03 +0000 | [diff] [blame] | 530 | |
reed@android.com | 49f0ff2 | 2009-03-19 21:52:42 +0000 | [diff] [blame] | 531 | dst->fRowBytes = dst->fBounds.width(); |
reed@android.com | 8a1c16f | 2008-12-17 15:59:43 +0000 | [diff] [blame] | 532 | dst->fFormat = SkMask::kA8_Format; |
halcanary | 96fcdcc | 2015-08-27 07:41:13 -0700 | [diff] [blame] | 533 | dst->fImage = nullptr; |
reed@android.com | 8a1c16f | 2008-12-17 15:59:43 +0000 | [diff] [blame] | 534 | |
reed@android.com | 0e3c664 | 2009-09-18 13:41:56 +0000 | [diff] [blame] | 535 | if (src.fImage) { |
reed@android.com | 543ed93 | 2009-04-24 12:43:40 +0000 | [diff] [blame] | 536 | size_t dstSize = dst->computeImageSize(); |
| 537 | if (0 == dstSize) { |
| 538 | return false; // too big to allocate, abort |
| 539 | } |
| 540 | |
reed@android.com | 8a1c16f | 2008-12-17 15:59:43 +0000 | [diff] [blame] | 541 | int sw = src.fBounds.width(); |
| 542 | int sh = src.fBounds.height(); |
| 543 | const uint8_t* sp = src.fImage; |
reed@android.com | 543ed93 | 2009-04-24 12:43:40 +0000 | [diff] [blame] | 544 | uint8_t* dp = SkMask::AllocImage(dstSize); |
reed@android.com | 8a1c16f | 2008-12-17 15:59:43 +0000 | [diff] [blame] | 545 | SkAutoTCallVProc<uint8_t, SkMask_FreeImage> autoCall(dp); |
| 546 | |
| 547 | // build the blurry destination |
commit-bot@chromium.org | 0a1c387 | 2013-06-11 15:23:42 +0000 | [diff] [blame] | 548 | SkAutoTMalloc<uint8_t> tmpBuffer(dstSize); |
| 549 | uint8_t* tp = tmpBuffer.get(); |
| 550 | int w = sw, h = sh; |
skia.committer@gmail.com | d454ec1 | 2013-02-21 07:15:03 +0000 | [diff] [blame] | 551 | |
commit-bot@chromium.org | 0a1c387 | 2013-06-11 15:23:42 +0000 | [diff] [blame] | 552 | if (outerWeight == 255) { |
| 553 | int loRadius, hiRadius; |
| 554 | get_adjusted_radii(passRadius, &loRadius, &hiRadius); |
commit-bot@chromium.org | e396455 | 2014-04-28 16:25:35 +0000 | [diff] [blame] | 555 | if (kHigh_SkBlurQuality == quality) { |
commit-bot@chromium.org | 0a1c387 | 2013-06-11 15:23:42 +0000 | [diff] [blame] | 556 | // Do three X blurs, with a transpose on the final one. |
| 557 | w = boxBlur(sp, src.fRowBytes, tp, loRadius, hiRadius, w, h, false); |
| 558 | w = boxBlur(tp, w, dp, hiRadius, loRadius, w, h, false); |
| 559 | w = boxBlur(dp, w, tp, hiRadius, hiRadius, w, h, true); |
| 560 | // Do three Y blurs, with a transpose on the final one. |
| 561 | h = boxBlur(tp, h, dp, loRadius, hiRadius, h, w, false); |
| 562 | h = boxBlur(dp, h, tp, hiRadius, loRadius, h, w, false); |
| 563 | h = boxBlur(tp, h, dp, hiRadius, hiRadius, h, w, true); |
senorblanco@chromium.org | 908276b | 2012-11-15 20:27:35 +0000 | [diff] [blame] | 564 | } else { |
commit-bot@chromium.org | 0a1c387 | 2013-06-11 15:23:42 +0000 | [diff] [blame] | 565 | w = boxBlur(sp, src.fRowBytes, tp, rx, rx, w, h, true); |
| 566 | h = boxBlur(tp, h, dp, ry, ry, h, w, true); |
senorblanco@chromium.org | 71f0f34 | 2012-11-13 20:35:21 +0000 | [diff] [blame] | 567 | } |
| 568 | } else { |
commit-bot@chromium.org | e396455 | 2014-04-28 16:25:35 +0000 | [diff] [blame] | 569 | if (kHigh_SkBlurQuality == quality) { |
commit-bot@chromium.org | 0a1c387 | 2013-06-11 15:23:42 +0000 | [diff] [blame] | 570 | // Do three X blurs, with a transpose on the final one. |
| 571 | w = boxBlurInterp(sp, src.fRowBytes, tp, rx, w, h, false, outerWeight); |
| 572 | w = boxBlurInterp(tp, w, dp, rx, w, h, false, outerWeight); |
| 573 | w = boxBlurInterp(dp, w, tp, rx, w, h, true, outerWeight); |
| 574 | // Do three Y blurs, with a transpose on the final one. |
| 575 | h = boxBlurInterp(tp, h, dp, ry, h, w, false, outerWeight); |
| 576 | h = boxBlurInterp(dp, h, tp, ry, h, w, false, outerWeight); |
| 577 | h = boxBlurInterp(tp, h, dp, ry, h, w, true, outerWeight); |
| 578 | } else { |
| 579 | w = boxBlurInterp(sp, src.fRowBytes, tp, rx, w, h, true, outerWeight); |
| 580 | h = boxBlurInterp(tp, h, dp, ry, h, w, true, outerWeight); |
senorblanco@chromium.org | 4868e6b | 2011-02-18 19:03:01 +0000 | [diff] [blame] | 581 | } |
reed@android.com | 8a1c16f | 2008-12-17 15:59:43 +0000 | [diff] [blame] | 582 | } |
| 583 | |
| 584 | dst->fImage = dp; |
| 585 | // if need be, alloc the "real" dst (same size as src) and copy/merge |
| 586 | // the blur into it (applying the src) |
commit-bot@chromium.org | e396455 | 2014-04-28 16:25:35 +0000 | [diff] [blame] | 587 | if (style == kInner_SkBlurStyle) { |
reed@android.com | 0e3c664 | 2009-09-18 13:41:56 +0000 | [diff] [blame] | 588 | // now we allocate the "real" dst, mirror the size of src |
reed@android.com | 543ed93 | 2009-04-24 12:43:40 +0000 | [diff] [blame] | 589 | size_t srcSize = src.computeImageSize(); |
| 590 | if (0 == srcSize) { |
| 591 | return false; // too big to allocate, abort |
| 592 | } |
| 593 | dst->fImage = SkMask::AllocImage(srcSize); |
reed@android.com | 0e3c664 | 2009-09-18 13:41:56 +0000 | [diff] [blame] | 594 | merge_src_with_blur(dst->fImage, src.fRowBytes, |
| 595 | sp, src.fRowBytes, |
reed@google.com | 03016a3 | 2011-08-12 14:59:59 +0000 | [diff] [blame] | 596 | dp + passCount * (rx + ry * dst->fRowBytes), |
| 597 | dst->fRowBytes, sw, sh); |
reed@android.com | 8a1c16f | 2008-12-17 15:59:43 +0000 | [diff] [blame] | 598 | SkMask::FreeImage(dp); |
commit-bot@chromium.org | e396455 | 2014-04-28 16:25:35 +0000 | [diff] [blame] | 599 | } else if (style != kNormal_SkBlurStyle) { |
reed@google.com | 03016a3 | 2011-08-12 14:59:59 +0000 | [diff] [blame] | 600 | clamp_with_orig(dp + passCount * (rx + ry * dst->fRowBytes), |
| 601 | dst->fRowBytes, sp, src.fRowBytes, sw, sh, style); |
reed@android.com | 8a1c16f | 2008-12-17 15:59:43 +0000 | [diff] [blame] | 602 | } |
| 603 | (void)autoCall.detach(); |
| 604 | } |
| 605 | |
commit-bot@chromium.org | e396455 | 2014-04-28 16:25:35 +0000 | [diff] [blame] | 606 | if (style == kInner_SkBlurStyle) { |
reed@android.com | 8a1c16f | 2008-12-17 15:59:43 +0000 | [diff] [blame] | 607 | dst->fBounds = src.fBounds; // restore trimmed bounds |
reed@android.com | 0e3c664 | 2009-09-18 13:41:56 +0000 | [diff] [blame] | 608 | dst->fRowBytes = src.fRowBytes; |
reed@android.com | 8a1c16f | 2008-12-17 15:59:43 +0000 | [diff] [blame] | 609 | } |
| 610 | |
reed@android.com | 8a1c16f | 2008-12-17 15:59:43 +0000 | [diff] [blame] | 611 | return true; |
| 612 | } |
| 613 | |
humper@google.com | 7c7292c | 2013-01-04 20:29:03 +0000 | [diff] [blame] | 614 | /* Convolving a box with itself three times results in a piecewise |
| 615 | quadratic function: |
skia.committer@gmail.com | 8ae714b | 2013-01-05 02:02:05 +0000 | [diff] [blame] | 616 | |
humper@google.com | 7c7292c | 2013-01-04 20:29:03 +0000 | [diff] [blame] | 617 | 0 x <= -1.5 |
humper@google.com | a99a92c | 2013-02-20 16:42:06 +0000 | [diff] [blame] | 618 | 9/8 + 3/2 x + 1/2 x^2 -1.5 < x <= -.5 |
humper@google.com | 7c7292c | 2013-01-04 20:29:03 +0000 | [diff] [blame] | 619 | 3/4 - x^2 -.5 < x <= .5 |
| 620 | 9/8 - 3/2 x + 1/2 x^2 0.5 < x <= 1.5 |
| 621 | 0 1.5 < x |
skia.committer@gmail.com | d454ec1 | 2013-02-21 07:15:03 +0000 | [diff] [blame] | 622 | |
humper@google.com | a99a92c | 2013-02-20 16:42:06 +0000 | [diff] [blame] | 623 | Mathematica: |
skia.committer@gmail.com | d454ec1 | 2013-02-21 07:15:03 +0000 | [diff] [blame] | 624 | |
humper@google.com | a99a92c | 2013-02-20 16:42:06 +0000 | [diff] [blame] | 625 | g[x_] := Piecewise [ { |
| 626 | {9/8 + 3/2 x + 1/2 x^2 , -1.5 < x <= -.5}, |
| 627 | {3/4 - x^2 , -.5 < x <= .5}, |
| 628 | {9/8 - 3/2 x + 1/2 x^2 , 0.5 < x <= 1.5} |
| 629 | }, 0] |
skia.committer@gmail.com | 8ae714b | 2013-01-05 02:02:05 +0000 | [diff] [blame] | 630 | |
humper@google.com | 7c7292c | 2013-01-04 20:29:03 +0000 | [diff] [blame] | 631 | To get the profile curve of the blurred step function at the rectangle |
| 632 | edge, we evaluate the indefinite integral, which is piecewise cubic: |
skia.committer@gmail.com | 8ae714b | 2013-01-05 02:02:05 +0000 | [diff] [blame] | 633 | |
humper@google.com | 7c7292c | 2013-01-04 20:29:03 +0000 | [diff] [blame] | 634 | 0 x <= -1.5 |
humper@google.com | a99a92c | 2013-02-20 16:42:06 +0000 | [diff] [blame] | 635 | 9/16 + 9/8 x + 3/4 x^2 + 1/6 x^3 -1.5 < x <= -0.5 |
humper@google.com | 7c7292c | 2013-01-04 20:29:03 +0000 | [diff] [blame] | 636 | 1/2 + 3/4 x - 1/3 x^3 -.5 < x <= .5 |
humper@google.com | a99a92c | 2013-02-20 16:42:06 +0000 | [diff] [blame] | 637 | 7/16 + 9/8 x - 3/4 x^2 + 1/6 x^3 .5 < x <= 1.5 |
humper@google.com | 7c7292c | 2013-01-04 20:29:03 +0000 | [diff] [blame] | 638 | 1 1.5 < x |
skia.committer@gmail.com | d454ec1 | 2013-02-21 07:15:03 +0000 | [diff] [blame] | 639 | |
humper@google.com | a99a92c | 2013-02-20 16:42:06 +0000 | [diff] [blame] | 640 | in Mathematica code: |
skia.committer@gmail.com | d454ec1 | 2013-02-21 07:15:03 +0000 | [diff] [blame] | 641 | |
humper@google.com | a99a92c | 2013-02-20 16:42:06 +0000 | [diff] [blame] | 642 | gi[x_] := Piecewise[ { |
| 643 | { 0 , x <= -1.5 }, |
| 644 | { 9/16 + 9/8 x + 3/4 x^2 + 1/6 x^3, -1.5 < x <= -0.5 }, |
| 645 | { 1/2 + 3/4 x - 1/3 x^3 , -.5 < x <= .5}, |
| 646 | { 7/16 + 9/8 x - 3/4 x^2 + 1/6 x^3, .5 < x <= 1.5} |
| 647 | },1] |
humper@google.com | 7c7292c | 2013-01-04 20:29:03 +0000 | [diff] [blame] | 648 | */ |
| 649 | |
humper@google.com | a99a92c | 2013-02-20 16:42:06 +0000 | [diff] [blame] | 650 | static float gaussianIntegral(float x) { |
| 651 | if (x > 1.5f) { |
humper@google.com | 7c7292c | 2013-01-04 20:29:03 +0000 | [diff] [blame] | 652 | return 0.0f; |
| 653 | } |
humper@google.com | a99a92c | 2013-02-20 16:42:06 +0000 | [diff] [blame] | 654 | if (x < -1.5f) { |
humper@google.com | 7c7292c | 2013-01-04 20:29:03 +0000 | [diff] [blame] | 655 | return 1.0f; |
| 656 | } |
| 657 | |
| 658 | float x2 = x*x; |
| 659 | float x3 = x2*x; |
| 660 | |
jvanverth@google.com | 9c4e5ac | 2013-01-07 18:41:28 +0000 | [diff] [blame] | 661 | if ( x > 0.5f ) { |
humper@google.com | a99a92c | 2013-02-20 16:42:06 +0000 | [diff] [blame] | 662 | return 0.5625f - (x3 / 6.0f - 3.0f * x2 * 0.25f + 1.125f * x); |
humper@google.com | 7c7292c | 2013-01-04 20:29:03 +0000 | [diff] [blame] | 663 | } |
jvanverth@google.com | 9c4e5ac | 2013-01-07 18:41:28 +0000 | [diff] [blame] | 664 | if ( x > -0.5f ) { |
| 665 | return 0.5f - (0.75f * x - x3 / 3.0f); |
humper@google.com | 7c7292c | 2013-01-04 20:29:03 +0000 | [diff] [blame] | 666 | } |
jvanverth@google.com | 9c4e5ac | 2013-01-07 18:41:28 +0000 | [diff] [blame] | 667 | return 0.4375f + (-x3 / 6.0f - 3.0f * x2 * 0.25f - 1.125f * x); |
humper@google.com | 7c7292c | 2013-01-04 20:29:03 +0000 | [diff] [blame] | 668 | } |
| 669 | |
commit-bot@chromium.org | cf34bc0 | 2014-01-30 15:34:43 +0000 | [diff] [blame] | 670 | /* ComputeBlurProfile allocates and fills in an array of floating |
skia.committer@gmail.com | 8ae714b | 2013-01-05 02:02:05 +0000 | [diff] [blame] | 671 | point values between 0 and 255 for the profile signature of |
humper@google.com | 7c7292c | 2013-01-04 20:29:03 +0000 | [diff] [blame] | 672 | a blurred half-plane with the given blur radius. Since we're |
| 673 | going to be doing screened multiplications (i.e., 1 - (1-x)(1-y)) |
| 674 | all the time, we actually fill in the profile pre-inverted |
| 675 | (already done 255-x). |
skia.committer@gmail.com | 8ae714b | 2013-01-05 02:02:05 +0000 | [diff] [blame] | 676 | |
humper@google.com | 7c5d7b7 | 2013-03-11 20:16:28 +0000 | [diff] [blame] | 677 | It's the responsibility of the caller to delete the |
humper@google.com | 7c7292c | 2013-01-04 20:29:03 +0000 | [diff] [blame] | 678 | memory returned in profile_out. |
| 679 | */ |
| 680 | |
robertphillips | 30c4cae | 2015-09-15 10:20:55 -0700 | [diff] [blame] | 681 | uint8_t* SkBlurMask::ComputeBlurProfile(SkScalar sigma) { |
robertphillips@google.com | 7ce661d | 2013-08-27 16:14:03 +0000 | [diff] [blame] | 682 | int size = SkScalarCeilToInt(6*sigma); |
skia.committer@gmail.com | 2e71f16 | 2013-03-12 07:12:32 +0000 | [diff] [blame] | 683 | |
robertphillips | 5175b95 | 2015-10-04 08:36:51 -0700 | [diff] [blame^] | 684 | float center = 0.5f * size; |
halcanary | 385fe4d | 2015-08-26 13:07:48 -0700 | [diff] [blame] | 685 | uint8_t* profile = new uint8_t[size]; |
humper@google.com | 7c7292c | 2013-01-04 20:29:03 +0000 | [diff] [blame] | 686 | |
robertphillips@google.com | 7ce661d | 2013-08-27 16:14:03 +0000 | [diff] [blame] | 687 | float invr = 1.f/(2*sigma); |
humper@google.com | 7c7292c | 2013-01-04 20:29:03 +0000 | [diff] [blame] | 688 | |
| 689 | profile[0] = 255; |
humper@google.com | a99a92c | 2013-02-20 16:42:06 +0000 | [diff] [blame] | 690 | for (int x = 1 ; x < size ; ++x) { |
jvanverth@google.com | d98df1a | 2013-02-20 19:02:34 +0000 | [diff] [blame] | 691 | float scaled_x = (center - x - .5f) * invr; |
humper@google.com | a99a92c | 2013-02-20 16:42:06 +0000 | [diff] [blame] | 692 | float gi = gaussianIntegral(scaled_x); |
| 693 | profile[x] = 255 - (uint8_t) (255.f * gi); |
humper@google.com | 7c7292c | 2013-01-04 20:29:03 +0000 | [diff] [blame] | 694 | } |
| 695 | |
robertphillips | 30c4cae | 2015-09-15 10:20:55 -0700 | [diff] [blame] | 696 | return profile; |
humper@google.com | 7c7292c | 2013-01-04 20:29:03 +0000 | [diff] [blame] | 697 | } |
| 698 | |
skia.committer@gmail.com | 8ae714b | 2013-01-05 02:02:05 +0000 | [diff] [blame] | 699 | // TODO MAYBE: Maintain a profile cache to avoid recomputing this for |
humper@google.com | 7c7292c | 2013-01-04 20:29:03 +0000 | [diff] [blame] | 700 | // commonly used radii. Consider baking some of the most common blur radii |
| 701 | // directly in as static data? |
| 702 | |
| 703 | // Implementation adapted from Michael Herf's approach: |
| 704 | // http://stereopsis.com/shadowrect/ |
| 705 | |
commit-bot@chromium.org | cf34bc0 | 2014-01-30 15:34:43 +0000 | [diff] [blame] | 706 | uint8_t SkBlurMask::ProfileLookup(const uint8_t *profile, int loc, int blurred_width, int sharp_width) { |
humper@google.com | a99a92c | 2013-02-20 16:42:06 +0000 | [diff] [blame] | 707 | int dx = SkAbs32(((loc << 1) + 1) - blurred_width) - sharp_width; // how far are we from the original edge? |
| 708 | int ox = dx >> 1; |
| 709 | if (ox < 0) { |
| 710 | ox = 0; |
| 711 | } |
skia.committer@gmail.com | d454ec1 | 2013-02-21 07:15:03 +0000 | [diff] [blame] | 712 | |
humper@google.com | a99a92c | 2013-02-20 16:42:06 +0000 | [diff] [blame] | 713 | return profile[ox]; |
| 714 | } |
| 715 | |
skia.committer@gmail.com | 4c18e9f | 2014-01-31 03:01:59 +0000 | [diff] [blame] | 716 | void SkBlurMask::ComputeBlurredScanline(uint8_t *pixels, const uint8_t *profile, |
commit-bot@chromium.org | cf34bc0 | 2014-01-30 15:34:43 +0000 | [diff] [blame] | 717 | unsigned int width, SkScalar sigma) { |
| 718 | |
| 719 | unsigned int profile_size = SkScalarCeilToInt(6*sigma); |
| 720 | SkAutoTMalloc<uint8_t> horizontalScanline(width); |
| 721 | |
| 722 | unsigned int sw = width - profile_size; |
| 723 | // nearest odd number less than the profile size represents the center |
| 724 | // of the (2x scaled) profile |
| 725 | int center = ( profile_size & ~1 ) - 1; |
| 726 | |
| 727 | int w = sw - center; |
| 728 | |
| 729 | for (unsigned int x = 0 ; x < width ; ++x) { |
| 730 | if (profile_size <= sw) { |
| 731 | pixels[x] = ProfileLookup(profile, x, width, w); |
| 732 | } else { |
| 733 | float span = float(sw)/(2*sigma); |
| 734 | float giX = 1.5f - (x+.5f)/(2*sigma); |
| 735 | pixels[x] = (uint8_t) (255 * (gaussianIntegral(giX) - gaussianIntegral(giX + span))); |
| 736 | } |
skia.committer@gmail.com | 4c18e9f | 2014-01-31 03:01:59 +0000 | [diff] [blame] | 737 | } |
commit-bot@chromium.org | cf34bc0 | 2014-01-30 15:34:43 +0000 | [diff] [blame] | 738 | } |
| 739 | |
skia.committer@gmail.com | 7bd141d | 2013-08-28 07:01:18 +0000 | [diff] [blame] | 740 | bool SkBlurMask::BlurRect(SkScalar sigma, SkMask *dst, |
commit-bot@chromium.org | e396455 | 2014-04-28 16:25:35 +0000 | [diff] [blame] | 741 | const SkRect &src, SkBlurStyle style, |
robertphillips@google.com | 7ce661d | 2013-08-27 16:14:03 +0000 | [diff] [blame] | 742 | SkIPoint *margin, SkMask::CreateMode createMode) { |
| 743 | int profile_size = SkScalarCeilToInt(6*sigma); |
skia.committer@gmail.com | 2e71f16 | 2013-03-12 07:12:32 +0000 | [diff] [blame] | 744 | |
humper@google.com | a99a92c | 2013-02-20 16:42:06 +0000 | [diff] [blame] | 745 | int pad = profile_size/2; |
humper@google.com | 7c7292c | 2013-01-04 20:29:03 +0000 | [diff] [blame] | 746 | if (margin) { |
| 747 | margin->set( pad, pad ); |
| 748 | } |
skia.committer@gmail.com | d454ec1 | 2013-02-21 07:15:03 +0000 | [diff] [blame] | 749 | |
skia.committer@gmail.com | 2e71f16 | 2013-03-12 07:12:32 +0000 | [diff] [blame] | 750 | dst->fBounds.set(SkScalarRoundToInt(src.fLeft - pad), |
| 751 | SkScalarRoundToInt(src.fTop - pad), |
| 752 | SkScalarRoundToInt(src.fRight + pad), |
humper@google.com | 68a690c | 2013-03-11 21:16:20 +0000 | [diff] [blame] | 753 | SkScalarRoundToInt(src.fBottom + pad)); |
skia.committer@gmail.com | 8ae714b | 2013-01-05 02:02:05 +0000 | [diff] [blame] | 754 | |
humper@google.com | 7c7292c | 2013-01-04 20:29:03 +0000 | [diff] [blame] | 755 | dst->fRowBytes = dst->fBounds.width(); |
| 756 | dst->fFormat = SkMask::kA8_Format; |
halcanary | 96fcdcc | 2015-08-27 07:41:13 -0700 | [diff] [blame] | 757 | dst->fImage = nullptr; |
skia.committer@gmail.com | 2e71f16 | 2013-03-12 07:12:32 +0000 | [diff] [blame] | 758 | |
humper@google.com | 7c5d7b7 | 2013-03-11 20:16:28 +0000 | [diff] [blame] | 759 | int sw = SkScalarFloorToInt(src.width()); |
| 760 | int sh = SkScalarFloorToInt(src.height()); |
skia.committer@gmail.com | 2e71f16 | 2013-03-12 07:12:32 +0000 | [diff] [blame] | 761 | |
humper@google.com | 7c5d7b7 | 2013-03-11 20:16:28 +0000 | [diff] [blame] | 762 | if (createMode == SkMask::kJustComputeBounds_CreateMode) { |
commit-bot@chromium.org | e396455 | 2014-04-28 16:25:35 +0000 | [diff] [blame] | 763 | if (style == kInner_SkBlurStyle) { |
skia.committer@gmail.com | 2e71f16 | 2013-03-12 07:12:32 +0000 | [diff] [blame] | 764 | dst->fBounds.set(SkScalarRoundToInt(src.fLeft), |
| 765 | SkScalarRoundToInt(src.fTop), |
| 766 | SkScalarRoundToInt(src.fRight), |
humper@google.com | 68a690c | 2013-03-11 21:16:20 +0000 | [diff] [blame] | 767 | SkScalarRoundToInt(src.fBottom)); // restore trimmed bounds |
humper@google.com | 7c5d7b7 | 2013-03-11 20:16:28 +0000 | [diff] [blame] | 768 | dst->fRowBytes = sw; |
| 769 | } |
| 770 | return true; |
| 771 | } |
skia.committer@gmail.com | 2e71f16 | 2013-03-12 07:12:32 +0000 | [diff] [blame] | 772 | |
robertphillips | 30c4cae | 2015-09-15 10:20:55 -0700 | [diff] [blame] | 773 | SkAutoTDeleteArray<uint8_t> profile(ComputeBlurProfile(sigma)); |
skia.committer@gmail.com | 2e71f16 | 2013-03-12 07:12:32 +0000 | [diff] [blame] | 774 | |
humper@google.com | 7c7292c | 2013-01-04 20:29:03 +0000 | [diff] [blame] | 775 | size_t dstSize = dst->computeImageSize(); |
| 776 | if (0 == dstSize) { |
| 777 | return false; // too big to allocate, abort |
| 778 | } |
skia.committer@gmail.com | 8ae714b | 2013-01-05 02:02:05 +0000 | [diff] [blame] | 779 | |
humper@google.com | 7c7292c | 2013-01-04 20:29:03 +0000 | [diff] [blame] | 780 | uint8_t* dp = SkMask::AllocImage(dstSize); |
skia.committer@gmail.com | 8ae714b | 2013-01-05 02:02:05 +0000 | [diff] [blame] | 781 | |
humper@google.com | 7c7292c | 2013-01-04 20:29:03 +0000 | [diff] [blame] | 782 | dst->fImage = dp; |
skia.committer@gmail.com | 8ae714b | 2013-01-05 02:02:05 +0000 | [diff] [blame] | 783 | |
humper@google.com | a99a92c | 2013-02-20 16:42:06 +0000 | [diff] [blame] | 784 | int dstHeight = dst->fBounds.height(); |
| 785 | int dstWidth = dst->fBounds.width(); |
skia.committer@gmail.com | 8ae714b | 2013-01-05 02:02:05 +0000 | [diff] [blame] | 786 | |
humper@google.com | 7c7292c | 2013-01-04 20:29:03 +0000 | [diff] [blame] | 787 | uint8_t *outptr = dp; |
skia.committer@gmail.com | d454ec1 | 2013-02-21 07:15:03 +0000 | [diff] [blame] | 788 | |
humper@google.com | a99a92c | 2013-02-20 16:42:06 +0000 | [diff] [blame] | 789 | SkAutoTMalloc<uint8_t> horizontalScanline(dstWidth); |
commit-bot@chromium.org | cf34bc0 | 2014-01-30 15:34:43 +0000 | [diff] [blame] | 790 | SkAutoTMalloc<uint8_t> verticalScanline(dstHeight); |
skia.committer@gmail.com | 4c18e9f | 2014-01-31 03:01:59 +0000 | [diff] [blame] | 791 | |
robertphillips | 30c4cae | 2015-09-15 10:20:55 -0700 | [diff] [blame] | 792 | ComputeBlurredScanline(horizontalScanline, profile.get(), dstWidth, sigma); |
| 793 | ComputeBlurredScanline(verticalScanline, profile.get(), dstHeight, sigma); |
skia.committer@gmail.com | d454ec1 | 2013-02-21 07:15:03 +0000 | [diff] [blame] | 794 | |
humper@google.com | a99a92c | 2013-02-20 16:42:06 +0000 | [diff] [blame] | 795 | for (int y = 0 ; y < dstHeight ; ++y) { |
humper@google.com | a99a92c | 2013-02-20 16:42:06 +0000 | [diff] [blame] | 796 | for (int x = 0 ; x < dstWidth ; x++) { |
commit-bot@chromium.org | cf34bc0 | 2014-01-30 15:34:43 +0000 | [diff] [blame] | 797 | unsigned int maskval = SkMulDiv255Round(horizontalScanline[x], verticalScanline[y]); |
humper@google.com | 7c7292c | 2013-01-04 20:29:03 +0000 | [diff] [blame] | 798 | *(outptr++) = maskval; |
| 799 | } |
| 800 | } |
skia.committer@gmail.com | d454ec1 | 2013-02-21 07:15:03 +0000 | [diff] [blame] | 801 | |
commit-bot@chromium.org | e396455 | 2014-04-28 16:25:35 +0000 | [diff] [blame] | 802 | if (style == kInner_SkBlurStyle) { |
humper@google.com | a99a92c | 2013-02-20 16:42:06 +0000 | [diff] [blame] | 803 | // now we allocate the "real" dst, mirror the size of src |
jvanverth@google.com | d98df1a | 2013-02-20 19:02:34 +0000 | [diff] [blame] | 804 | size_t srcSize = (size_t)(src.width() * src.height()); |
humper@google.com | a99a92c | 2013-02-20 16:42:06 +0000 | [diff] [blame] | 805 | if (0 == srcSize) { |
| 806 | return false; // too big to allocate, abort |
| 807 | } |
| 808 | dst->fImage = SkMask::AllocImage(srcSize); |
| 809 | for (int y = 0 ; y < sh ; y++) { |
| 810 | uint8_t *blur_scanline = dp + (y+pad)*dstWidth + pad; |
| 811 | uint8_t *inner_scanline = dst->fImage + y*sw; |
| 812 | memcpy(inner_scanline, blur_scanline, sw); |
| 813 | } |
| 814 | SkMask::FreeImage(dp); |
| 815 | |
skia.committer@gmail.com | 2e71f16 | 2013-03-12 07:12:32 +0000 | [diff] [blame] | 816 | dst->fBounds.set(SkScalarRoundToInt(src.fLeft), |
| 817 | SkScalarRoundToInt(src.fTop), |
| 818 | SkScalarRoundToInt(src.fRight), |
humper@google.com | 68a690c | 2013-03-11 21:16:20 +0000 | [diff] [blame] | 819 | SkScalarRoundToInt(src.fBottom)); // restore trimmed bounds |
humper@google.com | a99a92c | 2013-02-20 16:42:06 +0000 | [diff] [blame] | 820 | dst->fRowBytes = sw; |
skia.committer@gmail.com | d454ec1 | 2013-02-21 07:15:03 +0000 | [diff] [blame] | 821 | |
commit-bot@chromium.org | e396455 | 2014-04-28 16:25:35 +0000 | [diff] [blame] | 822 | } else if (style == kOuter_SkBlurStyle) { |
humper@google.com | a99a92c | 2013-02-20 16:42:06 +0000 | [diff] [blame] | 823 | for (int y = pad ; y < dstHeight-pad ; y++) { |
| 824 | uint8_t *dst_scanline = dp + y*dstWidth + pad; |
| 825 | memset(dst_scanline, 0, sw); |
| 826 | } |
commit-bot@chromium.org | e396455 | 2014-04-28 16:25:35 +0000 | [diff] [blame] | 827 | } else if (style == kSolid_SkBlurStyle) { |
humper@google.com | d4d5730 | 2013-03-11 22:18:54 +0000 | [diff] [blame] | 828 | for (int y = pad ; y < dstHeight-pad ; y++) { |
| 829 | uint8_t *dst_scanline = dp + y*dstWidth + pad; |
| 830 | memset(dst_scanline, 0xff, sw); |
skia.committer@gmail.com | 2e71f16 | 2013-03-12 07:12:32 +0000 | [diff] [blame] | 831 | } |
humper@google.com | a99a92c | 2013-02-20 16:42:06 +0000 | [diff] [blame] | 832 | } |
| 833 | // normal and solid styles are the same for analytic rect blurs, so don't |
| 834 | // need to handle solid specially. |
| 835 | |
| 836 | return true; |
| 837 | } |
| 838 | |
commit-bot@chromium.org | a477154 | 2014-03-10 21:42:06 +0000 | [diff] [blame] | 839 | bool SkBlurMask::BlurRRect(SkScalar sigma, SkMask *dst, |
commit-bot@chromium.org | e396455 | 2014-04-28 16:25:35 +0000 | [diff] [blame] | 840 | const SkRRect &src, SkBlurStyle style, |
commit-bot@chromium.org | a477154 | 2014-03-10 21:42:06 +0000 | [diff] [blame] | 841 | SkIPoint *margin, SkMask::CreateMode createMode) { |
| 842 | // Temporary for now -- always fail, should cause caller to fall back |
| 843 | // to old path. Plumbing just to land API and parallelize effort. |
| 844 | |
| 845 | return false; |
robertphillips@google.com | 7ce661d | 2013-08-27 16:14:03 +0000 | [diff] [blame] | 846 | } |
commit-bot@chromium.org | a477154 | 2014-03-10 21:42:06 +0000 | [diff] [blame] | 847 | |
humper@google.com | a99a92c | 2013-02-20 16:42:06 +0000 | [diff] [blame] | 848 | // The "simple" blur is a direct implementation of separable convolution with a discrete |
| 849 | // gaussian kernel. It's "ground truth" in a sense; too slow to be used, but very |
| 850 | // useful for correctness comparisons. |
| 851 | |
robertphillips@google.com | 7ce661d | 2013-08-27 16:14:03 +0000 | [diff] [blame] | 852 | bool SkBlurMask::BlurGroundTruth(SkScalar sigma, SkMask* dst, const SkMask& src, |
commit-bot@chromium.org | e396455 | 2014-04-28 16:25:35 +0000 | [diff] [blame] | 853 | SkBlurStyle style, SkIPoint* margin) { |
skia.committer@gmail.com | d454ec1 | 2013-02-21 07:15:03 +0000 | [diff] [blame] | 854 | |
humper@google.com | a99a92c | 2013-02-20 16:42:06 +0000 | [diff] [blame] | 855 | if (src.fFormat != SkMask::kA8_Format) { |
| 856 | return false; |
| 857 | } |
| 858 | |
robertphillips@google.com | 7ce661d | 2013-08-27 16:14:03 +0000 | [diff] [blame] | 859 | float variance = sigma * sigma; |
humper@google.com | a99a92c | 2013-02-20 16:42:06 +0000 | [diff] [blame] | 860 | |
reed@google.com | e1ca705 | 2013-12-17 19:22:07 +0000 | [diff] [blame] | 861 | int windowSize = SkScalarCeilToInt(sigma*6); |
humper@google.com | a99a92c | 2013-02-20 16:42:06 +0000 | [diff] [blame] | 862 | // round window size up to nearest odd number |
| 863 | windowSize |= 1; |
| 864 | |
| 865 | SkAutoTMalloc<float> gaussWindow(windowSize); |
| 866 | |
| 867 | int halfWindow = windowSize >> 1; |
skia.committer@gmail.com | d454ec1 | 2013-02-21 07:15:03 +0000 | [diff] [blame] | 868 | |
humper@google.com | a99a92c | 2013-02-20 16:42:06 +0000 | [diff] [blame] | 869 | gaussWindow[halfWindow] = 1; |
skia.committer@gmail.com | d454ec1 | 2013-02-21 07:15:03 +0000 | [diff] [blame] | 870 | |
humper@google.com | a99a92c | 2013-02-20 16:42:06 +0000 | [diff] [blame] | 871 | float windowSum = 1; |
| 872 | for (int x = 1 ; x <= halfWindow ; ++x) { |
robertphillips@google.com | 3dfa4cc | 2013-09-05 16:39:03 +0000 | [diff] [blame] | 873 | float gaussian = expf(-x*x / (2*variance)); |
humper@google.com | a99a92c | 2013-02-20 16:42:06 +0000 | [diff] [blame] | 874 | gaussWindow[halfWindow + x] = gaussWindow[halfWindow-x] = gaussian; |
| 875 | windowSum += 2*gaussian; |
| 876 | } |
| 877 | |
| 878 | // leave the filter un-normalized for now; we will divide by the normalization |
| 879 | // sum later; |
skia.committer@gmail.com | d454ec1 | 2013-02-21 07:15:03 +0000 | [diff] [blame] | 880 | |
humper@google.com | a99a92c | 2013-02-20 16:42:06 +0000 | [diff] [blame] | 881 | int pad = halfWindow; |
| 882 | if (margin) { |
| 883 | margin->set( pad, pad ); |
| 884 | } |
| 885 | |
| 886 | dst->fBounds = src.fBounds; |
| 887 | dst->fBounds.outset(pad, pad); |
| 888 | |
| 889 | dst->fRowBytes = dst->fBounds.width(); |
| 890 | dst->fFormat = SkMask::kA8_Format; |
halcanary | 96fcdcc | 2015-08-27 07:41:13 -0700 | [diff] [blame] | 891 | dst->fImage = nullptr; |
humper@google.com | a99a92c | 2013-02-20 16:42:06 +0000 | [diff] [blame] | 892 | |
| 893 | if (src.fImage) { |
| 894 | |
| 895 | size_t dstSize = dst->computeImageSize(); |
| 896 | if (0 == dstSize) { |
| 897 | return false; // too big to allocate, abort |
| 898 | } |
skia.committer@gmail.com | d454ec1 | 2013-02-21 07:15:03 +0000 | [diff] [blame] | 899 | |
humper@google.com | a99a92c | 2013-02-20 16:42:06 +0000 | [diff] [blame] | 900 | int srcWidth = src.fBounds.width(); |
| 901 | int srcHeight = src.fBounds.height(); |
| 902 | int dstWidth = dst->fBounds.width(); |
skia.committer@gmail.com | d454ec1 | 2013-02-21 07:15:03 +0000 | [diff] [blame] | 903 | |
humper@google.com | a99a92c | 2013-02-20 16:42:06 +0000 | [diff] [blame] | 904 | const uint8_t* srcPixels = src.fImage; |
| 905 | uint8_t* dstPixels = SkMask::AllocImage(dstSize); |
| 906 | SkAutoTCallVProc<uint8_t, SkMask_FreeImage> autoCall(dstPixels); |
| 907 | |
| 908 | // do the actual blur. First, make a padded copy of the source. |
| 909 | // use double pad so we never have to check if we're outside anything |
skia.committer@gmail.com | d454ec1 | 2013-02-21 07:15:03 +0000 | [diff] [blame] | 910 | |
humper@google.com | a99a92c | 2013-02-20 16:42:06 +0000 | [diff] [blame] | 911 | int padWidth = srcWidth + 4*pad; |
| 912 | int padHeight = srcHeight; |
| 913 | int padSize = padWidth * padHeight; |
skia.committer@gmail.com | d454ec1 | 2013-02-21 07:15:03 +0000 | [diff] [blame] | 914 | |
humper@google.com | a99a92c | 2013-02-20 16:42:06 +0000 | [diff] [blame] | 915 | SkAutoTMalloc<uint8_t> padPixels(padSize); |
| 916 | memset(padPixels, 0, padSize); |
skia.committer@gmail.com | d454ec1 | 2013-02-21 07:15:03 +0000 | [diff] [blame] | 917 | |
humper@google.com | a99a92c | 2013-02-20 16:42:06 +0000 | [diff] [blame] | 918 | for (int y = 0 ; y < srcHeight; ++y) { |
| 919 | uint8_t* padptr = padPixels + y * padWidth + 2*pad; |
| 920 | const uint8_t* srcptr = srcPixels + y * srcWidth; |
| 921 | memcpy(padptr, srcptr, srcWidth); |
| 922 | } |
skia.committer@gmail.com | d454ec1 | 2013-02-21 07:15:03 +0000 | [diff] [blame] | 923 | |
humper@google.com | a99a92c | 2013-02-20 16:42:06 +0000 | [diff] [blame] | 924 | // blur in X, transposing the result into a temporary floating point buffer. |
| 925 | // also double-pad the intermediate result so that the second blur doesn't |
| 926 | // have to do extra conditionals. |
skia.committer@gmail.com | d454ec1 | 2013-02-21 07:15:03 +0000 | [diff] [blame] | 927 | |
humper@google.com | a99a92c | 2013-02-20 16:42:06 +0000 | [diff] [blame] | 928 | int tmpWidth = padHeight + 4*pad; |
| 929 | int tmpHeight = padWidth - 2*pad; |
| 930 | int tmpSize = tmpWidth * tmpHeight; |
skia.committer@gmail.com | d454ec1 | 2013-02-21 07:15:03 +0000 | [diff] [blame] | 931 | |
humper@google.com | a99a92c | 2013-02-20 16:42:06 +0000 | [diff] [blame] | 932 | SkAutoTMalloc<float> tmpImage(tmpSize); |
| 933 | memset(tmpImage, 0, tmpSize*sizeof(tmpImage[0])); |
| 934 | |
| 935 | for (int y = 0 ; y < padHeight ; ++y) { |
| 936 | uint8_t *srcScanline = padPixels + y*padWidth; |
| 937 | for (int x = pad ; x < padWidth - pad ; ++x) { |
| 938 | float *outPixel = tmpImage + (x-pad)*tmpWidth + y + 2*pad; // transposed output |
| 939 | uint8_t *windowCenter = srcScanline + x; |
| 940 | for (int i = -pad ; i <= pad ; ++i) { |
| 941 | *outPixel += gaussWindow[pad+i]*windowCenter[i]; |
| 942 | } |
| 943 | *outPixel /= windowSum; |
skia.committer@gmail.com | d454ec1 | 2013-02-21 07:15:03 +0000 | [diff] [blame] | 944 | } |
humper@google.com | a99a92c | 2013-02-20 16:42:06 +0000 | [diff] [blame] | 945 | } |
skia.committer@gmail.com | d454ec1 | 2013-02-21 07:15:03 +0000 | [diff] [blame] | 946 | |
humper@google.com | a99a92c | 2013-02-20 16:42:06 +0000 | [diff] [blame] | 947 | // blur in Y; now filling in the actual desired destination. We have to do |
skia.committer@gmail.com | d454ec1 | 2013-02-21 07:15:03 +0000 | [diff] [blame] | 948 | // the transpose again; these transposes guarantee that we read memory in |
humper@google.com | a99a92c | 2013-02-20 16:42:06 +0000 | [diff] [blame] | 949 | // linear order. |
skia.committer@gmail.com | d454ec1 | 2013-02-21 07:15:03 +0000 | [diff] [blame] | 950 | |
humper@google.com | a99a92c | 2013-02-20 16:42:06 +0000 | [diff] [blame] | 951 | for (int y = 0 ; y < tmpHeight ; ++y) { |
| 952 | float *srcScanline = tmpImage + y*tmpWidth; |
| 953 | for (int x = pad ; x < tmpWidth - pad ; ++x) { |
| 954 | float *windowCenter = srcScanline + x; |
| 955 | float finalValue = 0; |
| 956 | for (int i = -pad ; i <= pad ; ++i) { |
| 957 | finalValue += gaussWindow[pad+i]*windowCenter[i]; |
| 958 | } |
| 959 | finalValue /= windowSum; |
| 960 | uint8_t *outPixel = dstPixels + (x-pad)*dstWidth + y; // transposed output |
| 961 | int integerPixel = int(finalValue + 0.5f); |
| 962 | *outPixel = SkClampMax( SkClampPos(integerPixel), 255 ); |
| 963 | } |
| 964 | } |
skia.committer@gmail.com | d454ec1 | 2013-02-21 07:15:03 +0000 | [diff] [blame] | 965 | |
humper@google.com | a99a92c | 2013-02-20 16:42:06 +0000 | [diff] [blame] | 966 | dst->fImage = dstPixels; |
| 967 | // if need be, alloc the "real" dst (same size as src) and copy/merge |
| 968 | // the blur into it (applying the src) |
commit-bot@chromium.org | e396455 | 2014-04-28 16:25:35 +0000 | [diff] [blame] | 969 | if (style == kInner_SkBlurStyle) { |
humper@google.com | a99a92c | 2013-02-20 16:42:06 +0000 | [diff] [blame] | 970 | // now we allocate the "real" dst, mirror the size of src |
| 971 | size_t srcSize = src.computeImageSize(); |
| 972 | if (0 == srcSize) { |
| 973 | return false; // too big to allocate, abort |
| 974 | } |
| 975 | dst->fImage = SkMask::AllocImage(srcSize); |
| 976 | merge_src_with_blur(dst->fImage, src.fRowBytes, |
| 977 | srcPixels, src.fRowBytes, |
| 978 | dstPixels + pad*dst->fRowBytes + pad, |
| 979 | dst->fRowBytes, srcWidth, srcHeight); |
| 980 | SkMask::FreeImage(dstPixels); |
commit-bot@chromium.org | e396455 | 2014-04-28 16:25:35 +0000 | [diff] [blame] | 981 | } else if (style != kNormal_SkBlurStyle) { |
humper@google.com | a99a92c | 2013-02-20 16:42:06 +0000 | [diff] [blame] | 982 | clamp_with_orig(dstPixels + pad*dst->fRowBytes + pad, |
| 983 | dst->fRowBytes, srcPixels, src.fRowBytes, srcWidth, srcHeight, style); |
| 984 | } |
| 985 | (void)autoCall.detach(); |
| 986 | } |
| 987 | |
commit-bot@chromium.org | e396455 | 2014-04-28 16:25:35 +0000 | [diff] [blame] | 988 | if (style == kInner_SkBlurStyle) { |
humper@google.com | a99a92c | 2013-02-20 16:42:06 +0000 | [diff] [blame] | 989 | dst->fBounds = src.fBounds; // restore trimmed bounds |
| 990 | dst->fRowBytes = src.fRowBytes; |
| 991 | } |
skia.committer@gmail.com | 8ae714b | 2013-01-05 02:02:05 +0000 | [diff] [blame] | 992 | |
humper@google.com | 7c7292c | 2013-01-04 20:29:03 +0000 | [diff] [blame] | 993 | return true; |
| 994 | } |