1 /* 2 * Copyright 2012 Google Inc. 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 8 #ifndef GrSWMaskHelper_DEFINED 9 #define GrSWMaskHelper_DEFINED 10 11 #include "GrColor.h" 12 #include "GrRenderTargetContext.h" 13 #include "SkAutoPixmapStorage.h" 14 #include "SkBitmap.h" 15 #include "SkDraw.h" 16 #include "SkMatrix.h" 17 #include "SkRasterClip.h" 18 #include "SkRegion.h" 19 #include "SkTypes.h" 20 21 class GrClip; 22 class GrPaint; 23 class GrShape; 24 class GrStyle; 25 class GrTexture; 26 struct GrUserStencilSettings; 27 28 /** 29 * The GrSWMaskHelper helps generate clip masks using the software rendering 30 * path. It is intended to be used as: 31 * 32 * GrSWMaskHelper helper(context); 33 * helper.init(...); 34 * 35 * draw one or more paths/rects specifying the required boolean ops 36 * 37 * toTexture(); // to get it from the internal bitmap to the GPU 38 * 39 * The result of this process will be the final mask (on the GPU) in the 40 * upper left hand corner of the texture. 41 */ 42 class GrSWMaskHelper : SkNoncopyable { 43 public: GrSWMaskHelper()44 GrSWMaskHelper() { } 45 46 // set up the internal state in preparation for draws. Since many masks 47 // may be accumulated in the helper during creation, "resultBounds" 48 // allows the caller to specify the region of interest - to limit the 49 // amount of work. 50 bool init(const SkIRect& resultBounds, const SkMatrix* matrix); 51 52 // Draw a single rect into the accumulation bitmap using the specified op 53 void drawRect(const SkRect& rect, SkRegion::Op op, GrAA, uint8_t alpha); 54 55 // Draw a single path into the accumuation bitmap using the specified op 56 void drawShape(const GrShape&, SkRegion::Op op, GrAA, uint8_t alpha); 57 58 sk_sp<GrTextureProxy> toTextureProxy(GrContext*, SkBackingFit fit); 59 60 // Convert mask generation results to a signed distance field 61 void toSDF(unsigned char* sdf); 62 63 // Reset the internal bitmap clear(uint8_t alpha)64 void clear(uint8_t alpha) { 65 fPixels.erase(SkColorSetARGB(alpha, 0xFF, 0xFF, 0xFF)); 66 } 67 68 // Canonical usage utility that draws a single path and uploads it 69 // to the GPU. The result is returned. 70 static sk_sp<GrTextureProxy> DrawShapeMaskToTexture(GrContext*, 71 const GrShape&, 72 const SkIRect& resultBounds, 73 GrAA, 74 SkBackingFit, 75 const SkMatrix* matrix); 76 77 // This utility draws a path mask generated by DrawShapeMaskToTexture using a provided paint. 78 // The rectangle is drawn in device space. The 'viewMatrix' will be used to ensure the correct 79 // local coords are provided to any fragment processors in the paint. 80 static void DrawToTargetWithShapeMask(sk_sp<GrTextureProxy>, 81 GrRenderTargetContext*, 82 GrPaint&& paint, 83 const GrUserStencilSettings& userStencilSettings, 84 const GrClip&, 85 const SkMatrix& viewMatrix, 86 const SkIPoint& textureOriginInDeviceSpace, 87 const SkIRect& deviceSpaceRectToDraw); 88 89 private: 90 SkMatrix fMatrix; 91 SkAutoPixmapStorage fPixels; 92 SkDraw fDraw; 93 SkRasterClip fRasterClip; 94 95 typedef SkNoncopyable INHERITED; 96 }; 97 98 #endif // GrSWMaskHelper_DEFINED 99