Home | History | Annotate | Download | only in batches 
      1 /*
      2  * Copyright 2015 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 
      9 #include "GrCopySurfaceBatch.h"
     10 
     11 // returns true if the read/written rect intersects the src/dst and false if not.
     12 bool GrCopySurfaceBatch::ClipSrcRectAndDstPoint(const GrSurface* dst,
     13                                                 const GrSurface* src,
     14                                                 const SkIRect& srcRect,
     15                                                 const SkIPoint& dstPoint,
     16                                                 SkIRect* clippedSrcRect,
     17                                                 SkIPoint* clippedDstPoint) {
     18     *clippedSrcRect = srcRect;
     19     *clippedDstPoint = dstPoint;
     20 
     21     // clip the left edge to src and dst bounds, adjusting dstPoint if necessary
     22     if (clippedSrcRect->fLeft < 0) {
     23         clippedDstPoint->fX -= clippedSrcRect->fLeft;
     24         clippedSrcRect->fLeft = 0;
     25     }
     26     if (clippedDstPoint->fX < 0) {
     27         clippedSrcRect->fLeft -= clippedDstPoint->fX;
     28         clippedDstPoint->fX = 0;
     29     }
     30 
     31     // clip the top edge to src and dst bounds, adjusting dstPoint if necessary
     32     if (clippedSrcRect->fTop < 0) {
     33         clippedDstPoint->fY -= clippedSrcRect->fTop;
     34         clippedSrcRect->fTop = 0;
     35     }
     36     if (clippedDstPoint->fY < 0) {
     37         clippedSrcRect->fTop -= clippedDstPoint->fY;
     38         clippedDstPoint->fY = 0;
     39     }
     40 
     41     // clip the right edge to the src and dst bounds.
     42     if (clippedSrcRect->fRight > src->width()) {
     43         clippedSrcRect->fRight = src->width();
     44     }
     45     if (clippedDstPoint->fX + clippedSrcRect->width() > dst->width()) {
     46         clippedSrcRect->fRight = clippedSrcRect->fLeft + dst->width() - clippedDstPoint->fX;
     47     }
     48 
     49     // clip the bottom edge to the src and dst bounds.
     50     if (clippedSrcRect->fBottom > src->height()) {
     51         clippedSrcRect->fBottom = src->height();
     52     }
     53     if (clippedDstPoint->fY + clippedSrcRect->height() > dst->height()) {
     54         clippedSrcRect->fBottom = clippedSrcRect->fTop + dst->height() - clippedDstPoint->fY;
     55     }
     56 
     57     // The above clipping steps may have inverted the rect if it didn't intersect either the src or
     58     // dst bounds.
     59     return !clippedSrcRect->isEmpty();
     60 }
     61 
     62 GrBatch* GrCopySurfaceBatch::Create(GrSurface* dst, GrSurface* src, const SkIRect& srcRect,
     63                                     const SkIPoint& dstPoint) {
     64     SkASSERT(dst);
     65     SkASSERT(src);
     66 
     67     SkIRect clippedSrcRect;
     68     SkIPoint clippedDstPoint;
     69     // If the rect is outside the src or dst then we've already succeeded.
     70     if (!ClipSrcRectAndDstPoint(dst, src, srcRect, dstPoint, &clippedSrcRect, &clippedDstPoint)) {
     71         return nullptr;
     72     }
     73     return new GrCopySurfaceBatch(dst, src, clippedSrcRect, clippedDstPoint);
     74 }
     75