Implement support for a Context parameter in image filters

src/gpu/SkGpuDevice.cpp

 /*
  * Copyright 2011 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "SkGpuDevice.h"
 
 #include "effects/GrBicubicEffect.h"
@@ skipping 1570 matching lines @@
     bool alphaOnly = !(SkBitmap::kA8_Config == bitmap.config());
     if (!skPaint2GrPaintNoShader(this, paint, alphaOnly, false, &grPaint)) {
         return;
     }
 
     fContext->drawRectToRect(grPaint, dstRect, paintRect, NULL);
 }
 
 static bool filter_texture(SkBaseDevice* device, GrContext* context,
                            GrTexture* texture, const SkImageFilter* filter,
-                           int w, int h, const SkMatrix& ctm, SkBitmap* result,
-                           SkIPoint* offset) {
+                           int w, int h, const SkImageFilter::Context& ctx,
+                           SkBitmap* result, SkIPoint* offset) {
     SkASSERT(filter);
     SkDeviceImageFilterProxy proxy(device);
 
     if (filter->canFilterImageGPU()) {
         // Save the render target and set it to NULL, so we don't accidentally draw to it in the
         // filter.  Also set the clip wide open and the matrix to identity.
         GrContext::AutoWideOpenIdentityDraw awo(context, NULL);
-        return filter->filterImageGPU(&proxy, wrap_texture(texture), ctm, result, offset);
+        return filter->filterImageGPU(&proxy, wrap_texture(texture), ctx, result, offset);
     } else {
         return false;
     }
 }
 
 void SkGpuDevice::drawSprite(const SkDraw& draw, const SkBitmap& bitmap,
                              int left, int top, const SkPaint& paint) {
     // drawSprite is defined to be in device coords.
     CHECK_SHOULD_DRAW(draw, true);
 
@@ skipping 10 matching lines @@
     SkAutoCachedTexture act(this, bitmap, NULL, &texture);
 
     SkImageFilter* filter = paint.getImageFilter();
     // This bitmap will own the filtered result as a texture.
     SkBitmap filteredBitmap;
 
     if (NULL != filter) {
         SkIPoint offset = SkIPoint::Make(0, 0);
         SkMatrix matrix(*draw.fMatrix);
         matrix.postTranslate(SkIntToScalar(-left), SkIntToScalar(-top));
-        if (filter_texture(this, fContext, texture, filter, w, h, matrix, &filteredBitmap,
+        SkIRect clipBounds = SkIRect::MakeWH(bitmap.width(), bitmap.height());
+        SkImageFilter::Context ctx(matrix, clipBounds);
+        if (filter_texture(this, fContext, texture, filter, w, h, ctx, &filteredBitmap,
                            &offset)) {
             texture = (GrTexture*) filteredBitmap.getTexture();
             w = filteredBitmap.width();
             h = filteredBitmap.height();
             left += offset.x();
             top += offset.y();
         } else {
             return;
         }
     }
@@ skipping 85 matching lines @@
     int h = bm.height();
 
     SkImageFilter* filter = paint.getImageFilter();
     // This bitmap will own the filtered result as a texture.
     SkBitmap filteredBitmap;
 
     if (NULL != filter) {
         SkIPoint offset = SkIPoint::Make(0, 0);
         SkMatrix matrix(*draw.fMatrix);
         matrix.postTranslate(SkIntToScalar(-x), SkIntToScalar(-y));
-        if (filter_texture(this, fContext, devTex, filter, w, h, matrix, &filteredBitmap,
+        SkIRect clipBounds = SkIRect::MakeWH(devTex->width(), devTex->height());
+        SkImageFilter::Context ctx(matrix, clipBounds);
+        if (filter_texture(this, fContext, devTex, filter, w, h, ctx, &filteredBitmap,
                            &offset)) {
             devTex = filteredBitmap.getTexture();
             w = filteredBitmap.width();
             h = filteredBitmap.height();
             x += offset.fX;
             y += offset.fY;
         } else {
             return;
         }
     }
@@ skipping 16 matching lines @@
                                     SK_Scalar1 * h / devTex->height());
 
     fContext->drawRectToRect(grPaint, dstRect, srcRect);
 }
 
 bool SkGpuDevice::canHandleImageFilter(const SkImageFilter* filter) {
     return filter->canFilterImageGPU();
 }
 
 bool SkGpuDevice::filterImage(const SkImageFilter* filter, const SkBitmap& src,
-                              const SkMatrix& ctm,
+                              const SkImageFilter::Context& ctx,
                               SkBitmap* result, SkIPoint* offset) {
     // want explicitly our impl, so guard against a subclass of us overriding it
     if (!this->SkGpuDevice::canHandleImageFilter(filter)) {
         return false;
     }
 
     SkAutoLockPixels alp(src, !src.getTexture());
     if (!src.getTexture() && !src.readyToDraw()) {
         return false;
     }
 
     GrTexture* texture;
     // We assume here that the filter will not attempt to tile the src. Otherwise, this cache lookup
     // must be pushed upstack.
     SkAutoCachedTexture act(this, src, NULL, &texture);
 
-    return filter_texture(this, fContext, texture, filter, src.width(), src.height(), ctm, result,
-                          offset);
+    return filter_texture(this, fContext, texture, filter, src.width(), src.height(), ctx,
+                          result, offset);
 }
 
 ///////////////////////////////////////////////////////////////////////////////
 
 // must be in SkCanvas::VertexMode order
 static const GrPrimitiveType gVertexMode2PrimitiveType[] = {
     kTriangles_GrPrimitiveType,
     kTriangleStrip_GrPrimitiveType,
     kTriangleFan_GrPrimitiveType,
 };
@@ skipping 189 matching lines @@
                          GrTexture* texture,
                          bool needClear)
     : SkBitmapDevice(make_bitmap(context, texture->asRenderTarget())) {
 
     SkASSERT(texture && texture->asRenderTarget());
     // This constructor is called from onCreateDevice. It has locked the RT in the texture
     // cache. We pass true for the third argument so that it will get unlocked.
     this->initFromRenderTarget(context, texture->asRenderTarget(), true);
     fNeedClear = needClear;
 }