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 "SkComposeShader.h" |
| 11 | #include "SkColorFilter.h" |
| 12 | #include "SkColorPriv.h" |
reed@google.com | 573f22b | 2011-11-30 19:17:15 +0000 | [diff] [blame] | 13 | #include "SkColorShader.h" |
reed@android.com | 8a1c16f | 2008-12-17 15:59:43 +0000 | [diff] [blame] | 14 | #include "SkXfermode.h" |
| 15 | |
reed@google.com | 82065d6 | 2011-02-07 15:30:46 +0000 | [diff] [blame] | 16 | /////////////////////////////////////////////////////////////////////////////// |
| 17 | |
| 18 | SkComposeShader::SkComposeShader(SkShader* sA, SkShader* sB, SkXfermode* mode) { |
reed@android.com | 8a1c16f | 2008-12-17 15:59:43 +0000 | [diff] [blame] | 19 | fShaderA = sA; sA->ref(); |
| 20 | fShaderB = sB; sB->ref(); |
| 21 | // mode may be null |
reed@google.com | 82065d6 | 2011-02-07 15:30:46 +0000 | [diff] [blame] | 22 | fMode = mode; |
| 23 | SkSafeRef(mode); |
reed@android.com | 8a1c16f | 2008-12-17 15:59:43 +0000 | [diff] [blame] | 24 | } |
| 25 | |
| 26 | SkComposeShader::SkComposeShader(SkFlattenableReadBuffer& buffer) : |
reed@google.com | 82065d6 | 2011-02-07 15:30:46 +0000 | [diff] [blame] | 27 | INHERITED(buffer) { |
reed@android.com | 8a1c16f | 2008-12-17 15:59:43 +0000 | [diff] [blame] | 28 | fShaderA = static_cast<SkShader*>(buffer.readFlattenable()); |
reed@google.com | 573f22b | 2011-11-30 19:17:15 +0000 | [diff] [blame] | 29 | if (NULL == fShaderA) { |
| 30 | fShaderA = SkNEW_ARGS(SkColorShader, (0)); |
| 31 | } |
reed@android.com | 8a1c16f | 2008-12-17 15:59:43 +0000 | [diff] [blame] | 32 | fShaderB = static_cast<SkShader*>(buffer.readFlattenable()); |
reed@google.com | 573f22b | 2011-11-30 19:17:15 +0000 | [diff] [blame] | 33 | if (NULL == fShaderB) { |
| 34 | fShaderB = SkNEW_ARGS(SkColorShader, (0)); |
| 35 | } |
reed@android.com | 8a1c16f | 2008-12-17 15:59:43 +0000 | [diff] [blame] | 36 | fMode = static_cast<SkXfermode*>(buffer.readFlattenable()); |
| 37 | } |
| 38 | |
reed@google.com | 82065d6 | 2011-02-07 15:30:46 +0000 | [diff] [blame] | 39 | SkComposeShader::~SkComposeShader() { |
| 40 | SkSafeUnref(fMode); |
reed@android.com | 8a1c16f | 2008-12-17 15:59:43 +0000 | [diff] [blame] | 41 | fShaderB->unref(); |
| 42 | fShaderA->unref(); |
| 43 | } |
| 44 | |
reed@google.com | 82065d6 | 2011-02-07 15:30:46 +0000 | [diff] [blame] | 45 | void SkComposeShader::beginSession() { |
reed@android.com | 8a1c16f | 2008-12-17 15:59:43 +0000 | [diff] [blame] | 46 | this->INHERITED::beginSession(); |
| 47 | fShaderA->beginSession(); |
| 48 | fShaderB->beginSession(); |
| 49 | } |
| 50 | |
reed@google.com | 82065d6 | 2011-02-07 15:30:46 +0000 | [diff] [blame] | 51 | void SkComposeShader::endSession() { |
reed@android.com | 8a1c16f | 2008-12-17 15:59:43 +0000 | [diff] [blame] | 52 | fShaderA->endSession(); |
| 53 | fShaderB->endSession(); |
| 54 | this->INHERITED::endSession(); |
| 55 | } |
| 56 | |
| 57 | class SkAutoAlphaRestore { |
| 58 | public: |
reed@google.com | 82065d6 | 2011-02-07 15:30:46 +0000 | [diff] [blame] | 59 | SkAutoAlphaRestore(SkPaint* paint, uint8_t newAlpha) { |
reed@android.com | 8a1c16f | 2008-12-17 15:59:43 +0000 | [diff] [blame] | 60 | fAlpha = paint->getAlpha(); |
| 61 | fPaint = paint; |
| 62 | paint->setAlpha(newAlpha); |
| 63 | } |
reed@google.com | 82065d6 | 2011-02-07 15:30:46 +0000 | [diff] [blame] | 64 | |
| 65 | ~SkAutoAlphaRestore() { |
reed@android.com | 8a1c16f | 2008-12-17 15:59:43 +0000 | [diff] [blame] | 66 | fPaint->setAlpha(fAlpha); |
| 67 | } |
| 68 | private: |
| 69 | SkPaint* fPaint; |
| 70 | uint8_t fAlpha; |
| 71 | }; |
| 72 | |
reed@google.com | 82065d6 | 2011-02-07 15:30:46 +0000 | [diff] [blame] | 73 | void SkComposeShader::flatten(SkFlattenableWriteBuffer& buffer) { |
reed@android.com | 8a1c16f | 2008-12-17 15:59:43 +0000 | [diff] [blame] | 74 | this->INHERITED::flatten(buffer); |
| 75 | buffer.writeFlattenable(fShaderA); |
| 76 | buffer.writeFlattenable(fShaderB); |
| 77 | buffer.writeFlattenable(fMode); |
| 78 | } |
| 79 | |
| 80 | /* We call setContext on our two worker shaders. However, we |
| 81 | always let them see opaque alpha, and if the paint really |
| 82 | is translucent, then we apply that after the fact. |
| 83 | */ |
| 84 | bool SkComposeShader::setContext(const SkBitmap& device, |
| 85 | const SkPaint& paint, |
reed@google.com | 82065d6 | 2011-02-07 15:30:46 +0000 | [diff] [blame] | 86 | const SkMatrix& matrix) { |
| 87 | if (!this->INHERITED::setContext(device, paint, matrix)) { |
reed@android.com | 8a1c16f | 2008-12-17 15:59:43 +0000 | [diff] [blame] | 88 | return false; |
reed@google.com | 82065d6 | 2011-02-07 15:30:46 +0000 | [diff] [blame] | 89 | } |
reed@android.com | 8a1c16f | 2008-12-17 15:59:43 +0000 | [diff] [blame] | 90 | |
| 91 | // we preconcat our localMatrix (if any) with the device matrix |
| 92 | // before calling our sub-shaders |
| 93 | |
| 94 | SkMatrix tmpM; |
reed@google.com | 82065d6 | 2011-02-07 15:30:46 +0000 | [diff] [blame] | 95 | |
reed@android.com | 8a1c16f | 2008-12-17 15:59:43 +0000 | [diff] [blame] | 96 | (void)this->getLocalMatrix(&tmpM); |
| 97 | tmpM.setConcat(matrix, tmpM); |
reed@google.com | 82065d6 | 2011-02-07 15:30:46 +0000 | [diff] [blame] | 98 | |
reed@android.com | 8a1c16f | 2008-12-17 15:59:43 +0000 | [diff] [blame] | 99 | SkAutoAlphaRestore restore(const_cast<SkPaint*>(&paint), 0xFF); |
| 100 | |
| 101 | return fShaderA->setContext(device, paint, tmpM) && |
| 102 | fShaderB->setContext(device, paint, tmpM); |
| 103 | } |
| 104 | |
| 105 | // larger is better (fewer times we have to loop), but we shouldn't |
| 106 | // take up too much stack-space (each element is 4 bytes) |
| 107 | #define TMP_COLOR_COUNT 64 |
| 108 | |
reed@google.com | 82065d6 | 2011-02-07 15:30:46 +0000 | [diff] [blame] | 109 | void SkComposeShader::shadeSpan(int x, int y, SkPMColor result[], int count) { |
reed@android.com | 8a1c16f | 2008-12-17 15:59:43 +0000 | [diff] [blame] | 110 | SkShader* shaderA = fShaderA; |
| 111 | SkShader* shaderB = fShaderB; |
| 112 | SkXfermode* mode = fMode; |
| 113 | unsigned scale = SkAlpha255To256(this->getPaintAlpha()); |
reed@google.com | 82065d6 | 2011-02-07 15:30:46 +0000 | [diff] [blame] | 114 | |
reed@android.com | 8a1c16f | 2008-12-17 15:59:43 +0000 | [diff] [blame] | 115 | SkPMColor tmp[TMP_COLOR_COUNT]; |
| 116 | |
reed@google.com | 82065d6 | 2011-02-07 15:30:46 +0000 | [diff] [blame] | 117 | if (NULL == mode) { // implied SRC_OVER |
reed@android.com | c4cae85 | 2009-09-23 15:06:10 +0000 | [diff] [blame] | 118 | // TODO: when we have a good test-case, should use SkBlitRow::Proc32 |
| 119 | // for these loops |
reed@android.com | 8a1c16f | 2008-12-17 15:59:43 +0000 | [diff] [blame] | 120 | do { |
| 121 | int n = count; |
reed@google.com | 82065d6 | 2011-02-07 15:30:46 +0000 | [diff] [blame] | 122 | if (n > TMP_COLOR_COUNT) { |
reed@android.com | 8a1c16f | 2008-12-17 15:59:43 +0000 | [diff] [blame] | 123 | n = TMP_COLOR_COUNT; |
reed@google.com | 82065d6 | 2011-02-07 15:30:46 +0000 | [diff] [blame] | 124 | } |
| 125 | |
reed@android.com | 8a1c16f | 2008-12-17 15:59:43 +0000 | [diff] [blame] | 126 | shaderA->shadeSpan(x, y, result, n); |
| 127 | shaderB->shadeSpan(x, y, tmp, n); |
| 128 | |
reed@google.com | 82065d6 | 2011-02-07 15:30:46 +0000 | [diff] [blame] | 129 | if (256 == scale) { |
| 130 | for (int i = 0; i < n; i++) { |
reed@android.com | 8a1c16f | 2008-12-17 15:59:43 +0000 | [diff] [blame] | 131 | result[i] = SkPMSrcOver(tmp[i], result[i]); |
reed@google.com | 82065d6 | 2011-02-07 15:30:46 +0000 | [diff] [blame] | 132 | } |
| 133 | } else { |
| 134 | for (int i = 0; i < n; i++) { |
| 135 | result[i] = SkAlphaMulQ(SkPMSrcOver(tmp[i], result[i]), |
| 136 | scale); |
| 137 | } |
reed@android.com | 8a1c16f | 2008-12-17 15:59:43 +0000 | [diff] [blame] | 138 | } |
reed@google.com | 82065d6 | 2011-02-07 15:30:46 +0000 | [diff] [blame] | 139 | |
reed@android.com | 8a1c16f | 2008-12-17 15:59:43 +0000 | [diff] [blame] | 140 | result += n; |
| 141 | x += n; |
| 142 | count -= n; |
| 143 | } while (count > 0); |
reed@google.com | 82065d6 | 2011-02-07 15:30:46 +0000 | [diff] [blame] | 144 | } else { // use mode for the composition |
reed@android.com | 8a1c16f | 2008-12-17 15:59:43 +0000 | [diff] [blame] | 145 | do { |
| 146 | int n = count; |
reed@google.com | 82065d6 | 2011-02-07 15:30:46 +0000 | [diff] [blame] | 147 | if (n > TMP_COLOR_COUNT) { |
reed@android.com | 8a1c16f | 2008-12-17 15:59:43 +0000 | [diff] [blame] | 148 | n = TMP_COLOR_COUNT; |
reed@google.com | 82065d6 | 2011-02-07 15:30:46 +0000 | [diff] [blame] | 149 | } |
| 150 | |
reed@android.com | 8a1c16f | 2008-12-17 15:59:43 +0000 | [diff] [blame] | 151 | shaderA->shadeSpan(x, y, result, n); |
| 152 | shaderB->shadeSpan(x, y, tmp, n); |
| 153 | mode->xfer32(result, tmp, n, NULL); |
| 154 | |
reed@google.com | 82065d6 | 2011-02-07 15:30:46 +0000 | [diff] [blame] | 155 | if (256 == scale) { |
| 156 | for (int i = 0; i < n; i++) { |
reed@android.com | 8a1c16f | 2008-12-17 15:59:43 +0000 | [diff] [blame] | 157 | result[i] = SkAlphaMulQ(result[i], scale); |
reed@google.com | 82065d6 | 2011-02-07 15:30:46 +0000 | [diff] [blame] | 158 | } |
reed@android.com | 8a1c16f | 2008-12-17 15:59:43 +0000 | [diff] [blame] | 159 | } |
| 160 | |
| 161 | result += n; |
| 162 | x += n; |
| 163 | count -= n; |
| 164 | } while (count > 0); |
| 165 | } |
| 166 | } |
reed@google.com | 82065d6 | 2011-02-07 15:30:46 +0000 | [diff] [blame] | 167 | |