| /* |
| * Copyright 2012 Google Inc. |
| * |
| * Use of this source code is governed by a BSD-style license that can be |
| * found in the LICENSE file. |
| */ |
| |
| #ifndef GrSWMaskHelper_DEFINED |
| #define GrSWMaskHelper_DEFINED |
| |
| #include "SkAutoPixmapStorage.h" |
| #include "GrColor.h" |
| #include "GrPipelineBuilder.h" |
| #include "SkBitmap.h" |
| #include "SkDraw.h" |
| #include "SkMatrix.h" |
| #include "SkRasterClip.h" |
| #include "SkRegion.h" |
| #include "SkTypes.h" |
| |
| class GrClip; |
| class GrTextureProvider; |
| class GrTexture; |
| class SkPath; |
| class SkStrokeRec; |
| class GrDrawTarget; |
| |
| /** |
| * The GrSWMaskHelper helps generate clip masks using the software rendering |
| * path. It is intended to be used as: |
| * |
| * GrSWMaskHelper helper(context); |
| * helper.init(...); |
| * |
| * draw one or more paths/rects specifying the required boolean ops |
| * |
| * toTexture(); // to get it from the internal bitmap to the GPU |
| * |
| * The result of this process will be the final mask (on the GPU) in the |
| * upper left hand corner of the texture. |
| */ |
| class GrSWMaskHelper : SkNoncopyable { |
| public: |
| GrSWMaskHelper(GrTextureProvider* texProvider) : fTexProvider(texProvider) { } |
| |
| // set up the internal state in preparation for draws. Since many masks |
| // may be accumulated in the helper during creation, "resultBounds" |
| // allows the caller to specify the region of interest - to limit the |
| // amount of work. |
| bool init(const SkIRect& resultBounds, const SkMatrix* matrix); |
| |
| // Draw a single rect into the accumulation bitmap using the specified op |
| void drawRect(const SkRect& rect, SkRegion::Op op, bool antiAlias, uint8_t alpha); |
| |
| // Draw a single path into the accumuation bitmap using the specified op |
| void drawPath(const SkPath& path, const GrStyle& style, SkRegion::Op op, |
| bool antiAlias, uint8_t alpha); |
| |
| // Move the mask generation results from the internal bitmap to the gpu. |
| void toTexture(GrTexture* texture); |
| |
| // Convert mask generation results to a signed distance field |
| void toSDF(unsigned char* sdf); |
| |
| // Reset the internal bitmap |
| void clear(uint8_t alpha) { |
| fPixels.erase(SkColorSetARGB(alpha, 0xFF, 0xFF, 0xFF)); |
| } |
| |
| // Canonical usage utility that draws a single path and uploads it |
| // to the GPU. The result is returned. |
| static GrTexture* DrawPathMaskToTexture(GrTextureProvider*, |
| const SkPath& path, |
| const GrStyle& style, |
| const SkIRect& resultBounds, |
| bool antiAlias, |
| const SkMatrix* matrix); |
| |
| // This utility routine is used to add a path's mask to some other draw. |
| // The ClipMaskManager uses it to accumulate clip masks while the |
| // GrSoftwarePathRenderer uses it to fulfill a drawPath call. |
| // It draws with "texture" as a path mask into "target" using "rect" as |
| // geometry and the current drawState. The current drawState is altered to |
| // accommodate the mask. |
| // Note that this method assumes that the GrPaint::kTotalStages slot in |
| // the draw state can be used to hold the mask texture stage. |
| // This method is really only intended to be used with the |
| // output of DrawPathMaskToTexture. |
| static void DrawToTargetWithPathMask(GrTexture* texture, |
| GrDrawTarget* target, |
| GrPipelineBuilder* pipelineBuilder, |
| const GrClip&, |
| GrColor, |
| const SkMatrix& viewMatrix, |
| const SkIRect& rect); |
| |
| private: |
| // Helper function to get a scratch texture suitable for capturing the |
| // result (i.e., right size & format) |
| GrTexture* createTexture(); |
| |
| GrTextureProvider* fTexProvider; |
| SkMatrix fMatrix; |
| SkAutoPixmapStorage fPixels; |
| SkDraw fDraw; |
| SkRasterClip fRasterClip; |
| |
| typedef SkNoncopyable INHERITED; |
| }; |
| |
| #endif // GrSWMaskHelper_DEFINED |