Rewrite GrTextureMaker to disentangle bitmap case from base class and give GPU object a say in what…

src/gpu/GrTextureParamsAdjuster.cpp

Index: src/gpu/GrTextureParamsAdjuster.cpp
diff --git a/src/gpu/GrTextureParamsAdjuster.cpp b/src/gpu/GrTextureParamsAdjuster.cpp
new file mode 100644
index 0000000000000000000000000000000000000000..9940f9e7d61261ddfe321c587ef7d951dc4071bb
--- /dev/null
+++ b/src/gpu/GrTextureParamsAdjuster.cpp
@@ -0,0 +1,152 @@
+/*
+ * Copyright 2015 Google Inc.
+ *
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+
+#include "GrTextureParamsAdjuster.h"
+
+#include "GrCaps.h"
+#include "GrContext.h"
+#include "GrDrawContext.h"
+#include "GrGpu.h"
+#include "GrTexture.h"
+#include "GrTextureParams.h"
+#include "GrTextureProvider.h"
+#include "SkCanvas.h"
+#include "SkGr.h"
+#include "SkGrPriv.h"
+
+typedef GrTextureParamsAdjuster::CopyParams CopyParams;
+
+static GrTexture* copy_on_gpu(GrTexture* inputTexture, const CopyParams& copyParams) {
+    GrContext* context = inputTexture->getContext();
+    SkASSERT(context);
+    const GrCaps* caps = context->caps();
+
+    // Either it's a cache miss or the original wasn't cached to begin with.
+    GrSurfaceDesc rtDesc = inputTexture->desc();
+    rtDesc.fFlags =  rtDesc.fFlags | kRenderTarget_GrSurfaceFlag;
+    rtDesc.fWidth  = copyParams.fWidth;
+    rtDesc.fHeight = copyParams.fHeight;
+    rtDesc.fConfig = GrMakePixelConfigUncompressed(rtDesc.fConfig);
+
+    // If the config isn't renderable try converting to either A8 or an 32 bit config. Otherwise,
+    // fail.
+    if (!caps->isConfigRenderable(rtDesc.fConfig, false)) {
+        if (GrPixelConfigIsAlphaOnly(rtDesc.fConfig)) {
+            if (caps->isConfigRenderable(kAlpha_8_GrPixelConfig, false)) {
+                rtDesc.fConfig = kAlpha_8_GrPixelConfig;
+            } else if (caps->isConfigRenderable(kSkia8888_GrPixelConfig, false)) {
+                rtDesc.fConfig = kSkia8888_GrPixelConfig;
+            } else {
+                return nullptr;
+            }
+        } else if (kRGB_GrColorComponentFlags ==
+                   (kRGB_GrColorComponentFlags & GrPixelConfigComponentMask(rtDesc.fConfig))) {
+            if (caps->isConfigRenderable(kSkia8888_GrPixelConfig, false)) {
+                rtDesc.fConfig = kSkia8888_GrPixelConfig;
+            } else {
+                return nullptr;
+            }
+        } else {
+            return nullptr;
+        }
+    }
+
+    SkAutoTUnref<GrTexture> copy(context->textureProvider()->createTexture(rtDesc, true));
+    if (!copy) {
+        return nullptr;
+    }
+
+    GrPaint paint;
+
+    // If filtering is not desired then we want to ensure all texels in the resampled image are
+    // copies of texels from the original.
+    GrTextureParams params(SkShader::kClamp_TileMode, copyParams.fFilter);
+    paint.addColorTextureProcessor(inputTexture, SkMatrix::I(), params);
+
+    SkRect rect = SkRect::MakeWH(SkIntToScalar(rtDesc.fWidth), SkIntToScalar(rtDesc.fHeight));
+    SkRect localRect = SkRect::MakeWH(1.f, 1.f);
+
+    SkAutoTUnref<GrDrawContext> drawContext(context->drawContext(copy->asRenderTarget()));
+    if (!drawContext) {
+        return nullptr;
+    }
+
+    drawContext->drawNonAARectToRect(GrClip::WideOpen(), paint, SkMatrix::I(), rect, localRect);
+    return copy.detach();
+}
+
+static SkBitmap copy_on_cpu(const SkBitmap& bmp, const CopyParams& copyParams) {
+    SkBitmap stretched;
+    stretched.allocN32Pixels(copyParams.fWidth, copyParams.fHeight);
+    SkCanvas canvas(stretched);
+    SkPaint paint;
+    switch (copyParams.fFilter) {
+        case GrTextureParams::kNone_FilterMode:
+            paint.setFilterQuality(kNone_SkFilterQuality);
+            break;
+        case GrTextureParams::kBilerp_FilterMode:
+            paint.setFilterQuality(kLow_SkFilterQuality);
+            break;
+        case GrTextureParams::kMipMap_FilterMode:
+            paint.setFilterQuality(kMedium_SkFilterQuality);
+            break;
+    }
+    SkRect dstRect = SkRect::MakeWH(SkIntToScalar(copyParams.fWidth),
+                                    SkIntToScalar(copyParams.fHeight));
+    canvas.drawBitmapRect(bmp, dstRect, &paint);
+    return stretched;
+}
+
+GrTexture* GrTextureParamsAdjuster::refTextureForParams(GrContext* ctx,
+                                                        const GrTextureParams& params) {
+    CopyParams copyParams;
+    if (!ctx->getGpu()->makeCopyForTextureParams(this->width(), this->height(), params,
+                                                 &copyParams)) {
+        return this->refOriginalTexture(ctx);
+    }
+    GrUniqueKey copyKey;
+    this->makeCopyKey(copyParams, &copyKey);
+    if (copyKey.isValid()) {
+        GrTexture* result = ctx->textureProvider()->findAndRefTextureByUniqueKey(copyKey);
+        if (result) {
+            return result;
+        }
+    }
+
+    GrTexture* result = this->generateTextureForParams(ctx, copyParams);
+    if (!result) {
+        return nullptr;
+    }
+
+    if (copyKey.isValid()) {
+        ctx->textureProvider()->assignUniqueKeyToTexture(copyKey, result);
+        this->didCacheCopy(copyKey);
+    }
+    return result;
+}
+
+GrTexture* GrTextureParamsAdjuster::generateTextureForParams(GrContext* ctx,
+                                                             const CopyParams& copyParams) {
+    if ((this->width() < ctx->caps()->minTextureSize() ||
+         this->height() < ctx->caps()->minTextureSize()) && !this->peekOriginalTexture())
+    {
+        // we can't trust our ability to use HW to perform the stretch, so we request
+        // a raster instead, and perform the stretch on the CPU.
+        SkBitmap bitmap;
+        if (!this->getROBitmap(&bitmap)) {
+            return nullptr;
+        }
+        SkBitmap stretchedBmp = copy_on_cpu(bitmap, copyParams);
+        return GrUploadBitmapToTexture(ctx, stretchedBmp);
+    } else {
+        SkAutoTUnref<GrTexture> original(this->refOriginalTexture(ctx));
+        if (!original) {
+            return nullptr;
+        }
+        return copy_on_gpu(original, copyParams);
+    }
+}