epoger@google.com | ec3ed6a | 2011-07-28 14:26:00 +0000 | [diff] [blame] | 1 | /* |
| 2 | * Copyright 2006 The Android Open Source Project |
| 3 | * |
| 4 | * Use of this source code is governed by a BSD-style license that can be |
| 5 | * found in the LICENSE file. |
| 6 | */ |
| 7 | |
reed@android.com | 8a1c16f | 2008-12-17 15:59:43 +0000 | [diff] [blame] | 8 | #ifndef SkBlurMask_DEFINED |
| 9 | #define SkBlurMask_DEFINED |
| 10 | |
commit-bot@chromium.org | e396455 | 2014-04-28 16:25:35 +0000 | [diff] [blame] | 11 | #include "SkBlurTypes.h" |
reed@android.com | 8a1c16f | 2008-12-17 15:59:43 +0000 | [diff] [blame] | 12 | #include "SkShader.h" |
humper@google.com | 7c5d7b7 | 2013-03-11 20:16:28 +0000 | [diff] [blame] | 13 | #include "SkMask.h" |
commit-bot@chromium.org | a477154 | 2014-03-10 21:42:06 +0000 | [diff] [blame] | 14 | #include "SkRRect.h" |
reed@android.com | 8a1c16f | 2008-12-17 15:59:43 +0000 | [diff] [blame] | 15 | |
| 16 | class SkBlurMask { |
| 17 | public: |
robertphillips | e80eb92 | 2015-12-17 11:33:12 -0800 | [diff] [blame] | 18 | static bool SK_WARN_UNUSED_RESULT BlurRect(SkScalar sigma, SkMask *dst, const SkRect &src, |
| 19 | SkBlurStyle, SkIPoint *margin = nullptr, |
| 20 | SkMask::CreateMode createMode = |
| 21 | SkMask::kComputeBoundsAndRenderImage_CreateMode); |
| 22 | static bool SK_WARN_UNUSED_RESULT BlurRRect(SkScalar sigma, SkMask *dst, const SkRRect &src, |
| 23 | SkBlurStyle, SkIPoint *margin = nullptr, |
| 24 | SkMask::CreateMode createMode = |
| 25 | SkMask::kComputeBoundsAndRenderImage_CreateMode); |
commit-bot@chromium.org | 3d8bf23 | 2014-04-28 19:49:24 +0000 | [diff] [blame] | 26 | |
| 27 | // forceQuality will prevent BoxBlur from falling back to the low quality approach when sigma |
| 28 | // is very small -- this can be used predict the margin bump ahead of time without completely |
| 29 | // replicating the internal logic. This permits not only simpler caching of blurred results, |
| 30 | // but also being able to predict precisely at what pixels the blurred profile of e.g. a |
| 31 | // rectangle will lie. |
| 32 | |
robertphillips | e80eb92 | 2015-12-17 11:33:12 -0800 | [diff] [blame] | 33 | static bool SK_WARN_UNUSED_RESULT BoxBlur(SkMask* dst, const SkMask& src, |
| 34 | SkScalar sigma, SkBlurStyle style, SkBlurQuality, |
| 35 | SkIPoint* margin = nullptr, |
| 36 | bool forceQuality = false); |
humper@google.com | a99a92c | 2013-02-20 16:42:06 +0000 | [diff] [blame] | 37 | |
| 38 | // the "ground truth" blur does a gaussian convolution; it's slow |
| 39 | // but useful for comparison purposes. |
robertphillips | e80eb92 | 2015-12-17 11:33:12 -0800 | [diff] [blame] | 40 | static bool SK_WARN_UNUSED_RESULT BlurGroundTruth(SkScalar sigma, SkMask* dst, |
| 41 | const SkMask& src, |
| 42 | SkBlurStyle, SkIPoint* margin = nullptr); |
humper@google.com | a99a92c | 2013-02-20 16:42:06 +0000 | [diff] [blame] | 43 | |
reed@google.com | daaafa6 | 2014-04-29 15:20:16 +0000 | [diff] [blame] | 44 | // If radius > 0, return the corresponding sigma, else return 0 |
robertphillips@google.com | 7ce661d | 2013-08-27 16:14:03 +0000 | [diff] [blame] | 45 | static SkScalar ConvertRadiusToSigma(SkScalar radius); |
reed@google.com | daaafa6 | 2014-04-29 15:20:16 +0000 | [diff] [blame] | 46 | // If sigma > 0.5, return the corresponding radius, else return 0 |
| 47 | static SkScalar ConvertSigmaToRadius(SkScalar sigma); |
skia.committer@gmail.com | 4c18e9f | 2014-01-31 03:01:59 +0000 | [diff] [blame] | 48 | |
commit-bot@chromium.org | cf34bc0 | 2014-01-30 15:34:43 +0000 | [diff] [blame] | 49 | /* Helper functions for analytic rectangle blurs */ |
skia.committer@gmail.com | 4c18e9f | 2014-01-31 03:01:59 +0000 | [diff] [blame] | 50 | |
commit-bot@chromium.org | cf34bc0 | 2014-01-30 15:34:43 +0000 | [diff] [blame] | 51 | /** Look up the intensity of the (one dimnensional) blurred half-plane. |
| 52 | @param profile The precomputed 1D blur profile; memory allocated by and managed by |
| 53 | ComputeBlurProfile below. |
skia.committer@gmail.com | 4c18e9f | 2014-01-31 03:01:59 +0000 | [diff] [blame] | 54 | @param loc the location to look up; The lookup will clamp invalid inputs, but |
commit-bot@chromium.org | cf34bc0 | 2014-01-30 15:34:43 +0000 | [diff] [blame] | 55 | meaningful data are available between 0 and blurred_width |
| 56 | @param blurred_width The width of the final, blurred rectangle |
| 57 | @param sharp_width The width of the original, unblurred rectangle. |
skia.committer@gmail.com | 4c18e9f | 2014-01-31 03:01:59 +0000 | [diff] [blame] | 58 | */ |
robertphillips | 30c4cae | 2015-09-15 10:20:55 -0700 | [diff] [blame] | 59 | static uint8_t ProfileLookup(const uint8_t* profile, int loc, int blurredWidth, int sharpWidth); |
skia.committer@gmail.com | 4c18e9f | 2014-01-31 03:01:59 +0000 | [diff] [blame] | 60 | |
commit-bot@chromium.org | cf34bc0 | 2014-01-30 15:34:43 +0000 | [diff] [blame] | 61 | /** Allocate memory for and populate the profile of a 1D blurred halfplane. The caller |
| 62 | must free the memory. The amount of memory allocated will be exactly 6*sigma bytes. |
| 63 | @param sigma The standard deviation of the gaussian blur kernel |
commit-bot@chromium.org | cf34bc0 | 2014-01-30 15:34:43 +0000 | [diff] [blame] | 64 | */ |
skia.committer@gmail.com | 4c18e9f | 2014-01-31 03:01:59 +0000 | [diff] [blame] | 65 | |
robertphillips | 30c4cae | 2015-09-15 10:20:55 -0700 | [diff] [blame] | 66 | static uint8_t* ComputeBlurProfile(SkScalar sigma); |
skia.committer@gmail.com | 4c18e9f | 2014-01-31 03:01:59 +0000 | [diff] [blame] | 67 | |
commit-bot@chromium.org | cf34bc0 | 2014-01-30 15:34:43 +0000 | [diff] [blame] | 68 | /** Compute an entire scanline of a blurred step function. This is a 1D helper that |
| 69 | will produce both the horizontal and vertical profiles of the blurry rectangle. |
| 70 | @param pixels Location to store the resulting pixel data; allocated and managed by caller |
| 71 | @param profile Precomputed blur profile computed by ComputeBlurProfile above. |
| 72 | @param width Size of the pixels array. |
| 73 | @param sigma Standard deviation of the gaussian blur kernel used to compute the profile; |
| 74 | this implicitly gives the size of the pixels array. |
| 75 | */ |
skia.committer@gmail.com | 4c18e9f | 2014-01-31 03:01:59 +0000 | [diff] [blame] | 76 | |
commit-bot@chromium.org | cf34bc0 | 2014-01-30 15:34:43 +0000 | [diff] [blame] | 77 | static void ComputeBlurredScanline(uint8_t* pixels, const uint8_t* profile, |
| 78 | unsigned int width, SkScalar sigma); |
skia.committer@gmail.com | 4c18e9f | 2014-01-31 03:01:59 +0000 | [diff] [blame] | 79 | |
| 80 | |
| 81 | |
reed@android.com | 8a1c16f | 2008-12-17 15:59:43 +0000 | [diff] [blame] | 82 | }; |
| 83 | |
| 84 | #endif |