Compute clipped src rect once in tiled bitmap draws

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/GrTextureDomainEffect.h"
@@ skipping 1014 matching lines @@
             return;
         }
     }
     clippedSrcRect.roundOut(clippedSrcIRect);
     SkIRect bmpBounds = SkIRect::MakeWH(bitmap.width(), bitmap.height());
     if (!clippedSrcIRect->intersect(bmpBounds)) {
         clippedSrcIRect->setEmpty();
     }
 }
 
-
 bool SkGpuDevice::shouldTileBitmap(const SkBitmap& bitmap,
                                    const GrTextureParams& params,
                                    const SkRect* srcRectPtr,
                                    int maxTileSize,
-                                   int* tileSize) const {
+                                   int* tileSize,
+                                   SkIRect* clippedSrcRect) const {
     // if bitmap is explictly texture backed then just use the texture
     if (NULL != bitmap.getTexture()) {
         return false;
     }
 
-    SkIRect clippedSrcRect;
-
     // if it's larger than the max tile size, then we have no choice but tiling.
     if (bitmap.width() > maxTileSize || bitmap.height() > maxTileSize) {
-        determine_clipped_src_rect(fContext, bitmap, srcRectPtr, &clippedSrcRect);
-        *tileSize = determine_tile_size(bitmap, clippedSrcRect, maxTileSize);
+        determine_clipped_src_rect(fContext, bitmap, srcRectPtr, clippedSrcRect);
+        *tileSize = determine_tile_size(bitmap, *clippedSrcRect, maxTileSize);
         return true;
     }
 
     if (bitmap.width() * bitmap.height() < 4 * kBmpSmallTileSize * kBmpSmallTileSize) {
         return false;
     }
 
     // if the entire texture is already in our cache then no reason to tile it
     if (GrIsBitmapInCache(fContext, bitmap, &params)) {
         return false;
     }
 
     // At this point we know we could do the draw by uploading the entire bitmap
     // as a texture. However, if the texture would be large compared to the
     // cache size and we don't require most of it for this draw then tile to
     // reduce the amount of upload and cache spill.
 
     // assumption here is that sw bitmap size is a good proxy for its size as
     // a texture
     size_t bmpSize = bitmap.getSize();
     size_t cacheSize;
     fContext->getTextureCacheLimits(NULL, &cacheSize);
     if (bmpSize < cacheSize / 2) {
         return false;
     }
 
     // Figure out how much of the src we will need based on the src rect and clipping.
-    determine_clipped_src_rect(fContext, bitmap, srcRectPtr, &clippedSrcRect);
+    determine_clipped_src_rect(fContext, bitmap, srcRectPtr, clippedSrcRect);
     *tileSize = kBmpSmallTileSize; // already know whole bitmap fits in one max sized tile.
-    size_t usedTileBytes = get_tile_count(clippedSrcRect, kBmpSmallTileSize) *
+    size_t usedTileBytes = get_tile_count(*clippedSrcRect, kBmpSmallTileSize) *
                            kBmpSmallTileSize * kBmpSmallTileSize;
 
     return usedTileBytes < 2 * bmpSize;
 }
 
 void SkGpuDevice::drawBitmap(const SkDraw& draw,
                              const SkBitmap& bitmap,
                              const SkMatrix& m,
                              const SkPaint& paint) {
     // We cannot call drawBitmapRect here since 'm' could be anything
@@ skipping 120 matching lines @@
     params.setFilterMode(textureFilterMode);
 
     int maxTileSize = fContext->getMaxTextureSize();
     if (SkPaint::kNone_FilterLevel != paint.getFilterLevel()) {
         // We may need a skosh more room if we have to bump out the tile
         // by 1 pixel all around
         maxTileSize -= 2;
     }
     int tileSize;
 
-    if (this->shouldTileBitmap(bitmap, params, srcRectPtr, maxTileSize, &tileSize)) {
-        this->drawTiledBitmap(bitmap, srcRect, params, paint, flags, tileSize);
+    SkIRect clippedSrcRect;
+    if (this->shouldTileBitmap(bitmap, params, srcRectPtr, maxTileSize, &tileSize,
+                               &clippedSrcRect)) {
+        this->drawTiledBitmap(bitmap, srcRect, clippedSrcRect, params, paint, flags, tileSize);
     } else {
         // take the simple case
         this->internalDrawBitmap(bitmap, srcRect, params, paint, flags);
     }
 }
 
 // Break 'bitmap' into several tiles to draw it since it has already
 // been determined to be too large to fit in VRAM
 void SkGpuDevice::drawTiledBitmap(const SkBitmap& bitmap,
                                   const SkRect& srcRect,
+                                  const SkIRect& clippedSrcIRect,
                                   const GrTextureParams& params,
                                   const SkPaint& paint,
                                   SkCanvas::DrawBitmapRectFlags flags,
                                   int tileSize) {
-
-    // compute clip bounds in local coordinates
-    SkRect clipRect;
-    {
-        const GrRenderTarget* rt = fContext->getRenderTarget();
-        clipRect.setWH(SkIntToScalar(rt->width()), SkIntToScalar(rt->height()));
-        if (!fContext->getClip()->fClipStack->intersectRectWithClip(&clipRect)) {
-            return;
-        }
-        SkMatrix inverse;
-        if (!fContext->getMatrix().invert(&inverse)) {
-            return;
-        }
-        inverse.mapRect(&clipRect);
-    }
+    SkRect clippedSrcRect = SkRect::MakeFromIRect(clippedSrcIRect);
 
     int nx = bitmap.width() / tileSize;
     int ny = bitmap.height() / tileSize;
     for (int x = 0; x <= nx; x++) {
         for (int y = 0; y <= ny; y++) {
             SkRect tileR;
             tileR.set(SkIntToScalar(x * tileSize),
                       SkIntToScalar(y * tileSize),
                       SkIntToScalar((x + 1) * tileSize),
                       SkIntToScalar((y + 1) * tileSize));
 
-            if (!SkRect::Intersects(tileR, clipRect)) {
+            if (!SkRect::Intersects(tileR, clippedSrcRect)) {
                 continue;
             }
 
             if (!tileR.intersect(srcRect)) {
                 continue;
             }
 
             SkBitmap tmpB;
             SkIRect iTileR;
             tileR.roundOut(&iTileR);
@@ skipping 588 matching lines @@
                          GrTexture* texture,
                          bool needClear)
     : SkBitmapDevice(make_bitmap(context, texture->asRenderTarget())) {
 
     SkASSERT(texture && texture->asRenderTarget());
     // This constructor is called from onCreateCompatibleDevice. 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;
 }