Add query for block dimensions of a given format

src/gpu/GrSWMaskHelper.cpp

 /*
  * Copyright 2012 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "GrSWMaskHelper.h"
 
 #include "GrDrawState.h"
 #include "GrDrawTargetCaps.h"
 #include "GrGpu.h"
 
 #include "SkData.h"
 #include "SkStrokeRec.h"
-#include "SkTextureCompressor.h"
 
 // TODO: try to remove this #include
 #include "GrContext.h"
 
 namespace {
 
 /*
  * Convert a boolean operation into a transfer mode code
  */
 SkXfermode::Mode op_to_mode(SkRegion::Op op) {
 
     static const SkXfermode::Mode modeMap[] = {
         SkXfermode::kDstOut_Mode,   // kDifference_Op
         SkXfermode::kModulate_Mode, // kIntersect_Op
         SkXfermode::kSrcOver_Mode,  // kUnion_Op
         SkXfermode::kXor_Mode,      // kXOR_Op
         SkXfermode::kClear_Mode,    // kReverseDifference_Op
         SkXfermode::kSrc_Mode,      // kReplace_Op
     };
 
     return modeMap[op];
 }
 
+static inline GrPixelConfig fmt_to_config(SkTextureCompressor::Format fmt) {
+    static const GrPixelConfig configMap[] = {
+        kLATC_GrPixelConfig,       // kLATC_Format,
+        kR11_EAC_GrPixelConfig,    // kR11_EAC_Format,
+        kASTC_12x12_GrPixelConfig  // kASTC_12x12_Format,
+    };
+    GR_STATIC_ASSERT(0 == SkTextureCompressor::kLATC_Format);
+    GR_STATIC_ASSERT(1 == SkTextureCompressor::kR11_EAC_Format);
+    GR_STATIC_ASSERT(2 == SkTextureCompressor::kASTC_12x12_Format);
+    GR_STATIC_ASSERT(SK_ARRAY_COUNT(configMap) == SkTextureCompressor::kFormatCnt);
+
+    return configMap[fmt];
+}
+
 }
 
 /**
  * Draw a single rect element of the clip stack into the accumulation bitmap
  */
 void GrSWMaskHelper::draw(const SkRect& rect, SkRegion::Op op,
                           bool antiAlias, uint8_t alpha) {
     SkPaint paint;
 
     SkXfermode* mode = SkXfermode::Create(op_to_mode(op));
@@ skipping 45 matching lines @@
         fMatrix = *matrix;
     } else {
         fMatrix.setIdentity();
     }
 
     // Now translate so the bound's UL corner is at the origin
     fMatrix.postTranslate(-resultBounds.fLeft * SK_Scalar1,
                           -resultBounds.fTop * SK_Scalar1);
     SkIRect bounds = SkIRect::MakeWH(resultBounds.width(),
                                      resultBounds.height());
+
 #if GR_COMPRESS_ALPHA_MASK
+    fCompressedFormat = SkTextureCompressor::kR11_EAC_Format;
+
     // Make sure that the width is a multiple of 16 so that we can use
     // specialized SIMD instructions that compress 4 blocks at a time.
-    const int cmpWidth = (bounds.fRight + 15) & ~15;
-    const int cmpHeight = (bounds.fBottom + 3) & ~3;
+    int dimX, dimY;
+    SkTextureCompressor::GetBlockDimensions(fCompressedFormat, &dimX, &dimY);
+    const int cmpWidth = dimX * ((bounds.fRight + (dimX - 1)) / dimX);
+    const int cmpHeight = dimY * ((bounds.fRight + (dimY - 1)) / dimY);
 #else
     const int cmpWidth = bounds.fRight;
     const int cmpHeight = bounds.fBottom;
 #endif
 
     if (!fBM.allocPixels(SkImageInfo::MakeA8(cmpWidth, cmpHeight))) {
         return false;
     }
 
     sk_bzero(fBM.getPixels(), fBM.getSafeSize());
 
     sk_bzero(&fDraw, sizeof(fDraw));
     fRasterClip.setRect(bounds);
     fDraw.fRC    = &fRasterClip;
     fDraw.fClip  = &fRasterClip.bwRgn();
     fDraw.fMatrix = &fMatrix;
     fDraw.fBitmap = &fBM;
     return true;
 }
 
 /**
  * Get a texture (from the texture cache) of the correct size & format.
  * Return true on success; false on failure.
  */
 bool GrSWMaskHelper::getTexture(GrAutoScratchTexture* texture) {
     GrTextureDesc desc;
     desc.fWidth = fBM.width();
     desc.fHeight = fBM.height();
-    desc.fConfig = kAlpha_8_GrPixelConfig;
 
 #if GR_COMPRESS_ALPHA_MASK
-    static const int kCompressedBlockSize = 4;
-    static const GrPixelConfig kCompressedConfig = kR11_EAC_GrPixelConfig;
 
-    if (desc.fWidth % kCompressedBlockSize == 0 &&
-        desc.fHeight % kCompressedBlockSize == 0) {
-        desc.fConfig = kCompressedConfig;
-    }
+#ifdef SK_DEBUG
+    int dimX, dimY;
+    SkTextureCompressor::GetBlockDimensions(fCompressedFormat, &dimX, &dimY);
+    SkASSERT((desc.fWidth % dimX) == 0);
+    SkASSERT((desc.fHeight % dimY) == 0);
+#endif
+
+    desc.fConfig = fmt_to_config(fCompressedFormat);
 
     // If this config isn't supported then we should fall back to A8
     if (!(fContext->getGpu()->caps()->isConfigTexturable(desc.fConfig))) {
         desc.fConfig = kAlpha_8_GrPixelConfig;
     }
+#else
+    desc.fConfig = kAlpha_8_GrPixelConfig;
 #endif
 
     texture->set(fContext, desc);
     return NULL != texture->texture();
 }
 
 void GrSWMaskHelper::sendTextureData(GrTexture *texture, const GrTextureDesc& desc,
                                      const void *data, int rowbytes) {
     // If we aren't reusing scratch textures we don't need to flush before
     // writing since no one else will be using 'texture'
@@ skipping 109 matching lines @@
     maskMatrix.preConcat(drawState->getViewMatrix());
 
     drawState->addCoverageEffect(
                          GrSimpleTextureEffect::Create(texture,
                                                        maskMatrix,
                                                        GrTextureParams::kNone_FilterMode,
                                                        kPosition_GrCoordSet))->unref();
 
     target->drawSimpleRect(dstRect);
 }