Revert "Create a semi-stable API for capturing the state of an SkCanvas and reconstructing that sta…

src/utils/SkCanvasStateUtils.cpp

Index: src/utils/SkCanvasStateUtils.cpp
diff --git a/src/utils/SkCanvasStateUtils.cpp b/src/utils/SkCanvasStateUtils.cpp
deleted file mode 100644
index 8abab6b5ae19805c9703b7c9e8833e1c76b88d1a..0000000000000000000000000000000000000000
--- a/src/utils/SkCanvasStateUtils.cpp
+++ /dev/null
@@ -1,339 +0,0 @@
-/*
- * Copyright 2013 Google Inc.
- *
- * Use of this source code is governed by a BSD-style license that can be
- * found in the LICENSE file.
- */
-
-#include "SkCanvasStateUtils.h"
-#include "SkCanvas.h"
-#include "SkDevice.h"
-#include "SkNWayCanvas.h"
-#include "SkWriter32.h"
-
-#define CANVAS_STATE_VERSION 1
-/*
- * WARNING: The structs below are part of a stable ABI and as such we explicitly
- * use unambigious primitives (e.g. int32_t instead of an enum).
- *
- * ANY CHANGES TO THE STRUCTS BELOW THAT IMPACT THE ABI SHOULD RESULT IN AN
- * UPDATE OF THE CANVAS_STATE_VERSION. SUCH CHANGES SHOULD ONLY BE MADE IF
- * ABSOLUTELY NECESSARY!
- */
-enum RasterConfigs {
-  kUnknown_RasterConfig   = 0,
-  kRGB_565_RasterConfig   = 1,
-  kARGB_8888_RasterConfig = 2
-};
-typedef int32_t RasterConfig;
-
-enum CanvasBackends {
-    kUnknown_CanvasBackend = 0,
-    kRaster_CanvasBackend  = 1,
-    kGPU_CanvasBackend     = 2,
-    kPDF_CanvasBackend     = 3
-};
-typedef int32_t CanvasBackend;
-
-struct ClipRect {
-    int32_t left, top, right, bottom;
-};
-
-struct SkMCState {
-    float matrix[9];
-    // NOTE: this only works for non-antialiased clips
-    int32_t clipRectCount;
-    ClipRect* clipRects;
-};
-
-// NOTE: If you add more members, bump CanvasState::version.
-struct SkCanvasLayerState {
-    CanvasBackend type;
-    int32_t x, y;
-    int32_t width;
-    int32_t height;
-
-    SkMCState mcState;
-
-    union {
-        struct {
-            RasterConfig config; // pixel format: a value from RasterConfigs.
-            uint32_t rowBytes;   // Number of bytes from start of one line to next.
-            void* pixels;        // The pixels, all (height * rowBytes) of them.
-        } raster;
-        struct {
-            int32_t textureID;
-        } gpu;
-    };
-};
-
-class SkCanvasState {
-public:
-    SkCanvasState(SkCanvas* canvas) {
-        SkASSERT(canvas);
-        version = CANVAS_STATE_VERSION;
-        width = canvas->getDeviceSize().width();
-        height = canvas->getDeviceSize().height();
-        layerCount = 0;
-        layers = NULL;
-        originalCanvas = SkRef(canvas);
-
-        mcState.clipRectCount = 0;
-        mcState.clipRects = NULL;
-    }
-
-    ~SkCanvasState() {
-        // loop through the layers and free the data allocated to the clipRects
-        for (int i = 0; i < layerCount; ++i) {
-            sk_free(layers[i].mcState.clipRects);
-        }
-
-        sk_free(mcState.clipRects);
-        sk_free(layers);
-
-        // it is now safe to free the canvas since there should be no remaining
-        // references to the content that is referenced by this canvas (e.g. pixels)
-        originalCanvas->unref();
-    }
-
-    /**
-     * The version this struct was built with.  This field must always appear
-     * first in the struct so that when the versions don't match (and the
-     * remaining contents and size are potentially different) we can still
-     * compare the version numbers.
-     */
-    int32_t version;
-
-    int32_t width;
-    int32_t height;
-
-    SkMCState mcState;
-
-    int32_t layerCount;
-    SkCanvasLayerState* layers;
-
-private:
-    SkCanvas* originalCanvas;
-};
-
-////////////////////////////////////////////////////////////////////////////////
-
-class ClipValidator : public SkCanvas::ClipVisitor {
-public:
-    ClipValidator() : fFailed(false) {}
-    bool failed() { return fFailed; }
-
-    // ClipVisitor
-    virtual void clipRect(const SkRect& rect, SkRegion::Op op, bool antialias) SK_OVERRIDE {
-        fFailed |= antialias;
-    }
-
-    virtual void clipPath(const SkPath&, SkRegion::Op, bool antialias) SK_OVERRIDE {
-        fFailed |= antialias;
-    }
-
-private:
-    bool fFailed;
-};
-
-static void setup_MC_state(SkMCState* state, const SkMatrix& matrix, const SkRegion& clip) {
-    // initialize the struct
-    state->clipRectCount = 0;
-
-    // capture the matrix
-    for (int i = 0; i < 9; i++) {
-        state->matrix[i] = matrix.get(i);
-    }
-
-    /*
-     * capture the clip
-     *
-     * storage is allocated on the stack for the first 4 rects. This value was
-     * chosen somewhat arbitrarily, but does allow us to represent simple clips
-     * and some more common complex clips (e.g. a clipRect with a sub-rect
-     * clipped out of its interior) without needing to malloc any additional memory.
-     */
-    const int clipBufferSize = 4 * sizeof(ClipRect);
-    char clipBuffer[clipBufferSize];
-    SkWriter32 clipWriter(sizeof(ClipRect), clipBuffer, clipBufferSize);
-
-    if (!clip.isEmpty()) {
-        // only returns the b/w clip so aa clips fail
-        SkRegion::Iterator clip_iterator(clip);
-        for (; !clip_iterator.done(); clip_iterator.next()) {
-            // this assumes the SkIRect is stored in l,t,r,b ordering which
-            // matches the ordering of our ClipRect struct
-            clipWriter.writeIRect(clip_iterator.rect());
-            state->clipRectCount++;
-        }
-    }
-
-    // allocate memory for the clip then and copy them to the struct
-    state->clipRects = (ClipRect*) sk_malloc_throw(clipWriter.size());
-    clipWriter.flatten(state->clipRects);
-}
-
-
-
-SkCanvasState* SkCanvasStateUtils::CaptureCanvasState(SkCanvas* canvas) {
-    SkASSERT(canvas);
-
-    // Check the clip can be decomposed into rectangles (i.e. no soft clips).
-    ClipValidator validator;
-    canvas->replayClips(&validator);
-    if (validator.failed()) {
-        SkDEBUGF(("CaptureCanvasState does not support canvases with antialiased clips.\n"));
-        return NULL;
-    }
-
-    SkAutoTDelete<SkCanvasState> canvasState(SkNEW_ARGS(SkCanvasState, (canvas)));
-
-    // decompose the total matrix and clip
-    setup_MC_state(&canvasState->mcState, canvas->getTotalMatrix(), canvas->getTotalClip());
-
-    /*
-     * decompose the layers
-     *
-     * storage is allocated on the stack for the first 3 layers. It is common in
-     * some view systems (e.g. Android) that a few non-clipped layers are present
-     * and we will not need to malloc any additional memory in those cases.
-     */
-    const int layerBufferSize = 3 * sizeof(SkCanvasLayerState);
-    char layerBuffer[layerBufferSize];
-    SkWriter32 layerWriter(sizeof(SkCanvasLayerState), layerBuffer, layerBufferSize);
-    int layerCount = 0;
-    for (SkCanvas::LayerIter layer(canvas, true/*skipEmptyClips*/); !layer.done(); layer.next()) {
-
-        // we currently only work for bitmap backed devices
-        const SkBitmap& bitmap = layer.device()->accessBitmap(true/*changePixels*/);
-        if (bitmap.empty() || bitmap.isNull() || !bitmap.lockPixelsAreWritable()) {
-            return NULL;
-        }
-
-        SkCanvasLayerState* layerState =
-                (SkCanvasLayerState*) layerWriter.reserve(sizeof(SkCanvasLayerState));
-        layerState->type = kRaster_CanvasBackend;
-        layerState->x = layer.x();
-        layerState->y = layer.y();
-        layerState->width = bitmap.width();
-        layerState->height = bitmap.height();
-
-        switch (bitmap.config()) {
-            case SkBitmap::kARGB_8888_Config:
-                layerState->raster.config = kARGB_8888_RasterConfig;
-                break;
-            case SkBitmap::kRGB_565_Config:
-                layerState->raster.config = kRGB_565_RasterConfig;
-                break;
-            default:
-                return NULL;
-        }
-        layerState->raster.rowBytes = bitmap.rowBytes();
-        layerState->raster.pixels = bitmap.getPixels();
-
-        setup_MC_state(&layerState->mcState, layer.matrix(), layer.clip());
-        layerCount++;
-    }
-
-    // allocate memory for the layers and then and copy them to the struct
-    SkASSERT(layerWriter.size() == layerCount * sizeof(SkCanvasLayerState));
-    canvasState->layerCount = layerCount;
-    canvasState->layers = (SkCanvasLayerState*) sk_malloc_throw(layerWriter.size());
-    layerWriter.flatten(canvasState->layers);
-
-    // for now, just ignore any client supplied DrawFilter.
-    if (canvas->getDrawFilter()) {
-        SkDEBUGF(("CaptureCanvasState will ignore the canvases draw filter.\n"));
-    }
-
-    return canvasState.detach();
-}
-
-////////////////////////////////////////////////////////////////////////////////
-
-static void setup_canvas_from_MC_state(const SkMCState& state, SkCanvas* canvas) {
-    // reconstruct the matrix
-    SkMatrix matrix;
-    for (int i = 0; i < 9; i++) {
-        matrix.set(i, state.matrix[i]);
-    }
-
-    // reconstruct the clip
-    SkRegion clip;
-    for (int i = 0; i < state.clipRectCount; ++i) {
-        clip.op(SkIRect::MakeLTRB(state.clipRects[i].left,
-                                  state.clipRects[i].top,
-                                  state.clipRects[i].right,
-                                  state.clipRects[i].bottom),
-                SkRegion::kUnion_Op);
-    }
-
-    canvas->setMatrix(matrix);
-    canvas->setClipRegion(clip);
-}
-
-static SkCanvas* create_canvas_from_canvas_layer(const SkCanvasLayerState& layerState) {
-    SkASSERT(kRaster_CanvasBackend == layerState.type);
-
-    SkBitmap bitmap;
-    SkBitmap::Config config =
-        layerState.raster.config == kARGB_8888_RasterConfig ? SkBitmap::kARGB_8888_Config :
-        layerState.raster.config == kRGB_565_RasterConfig ? SkBitmap::kRGB_565_Config :
-        SkBitmap::kNo_Config;
-
-    if (config == SkBitmap::kNo_Config) {
-        return NULL;
-    }
-
-    bitmap.setConfig(config, layerState.width, layerState.height,
-                     layerState.raster.rowBytes);
-    bitmap.setPixels(layerState.raster.pixels);
-
-    SkASSERT(!bitmap.empty());
-    SkASSERT(!bitmap.isNull());
-
-    // create a device & canvas
-    SkAutoTUnref<SkDevice> device(SkNEW_ARGS(SkDevice, (bitmap)));
-    SkAutoTUnref<SkCanvas> canvas(SkNEW_ARGS(SkCanvas, (device.get())));
-
-    // setup the matrix and clip
-    setup_canvas_from_MC_state(layerState.mcState, canvas.get());
-
-    return canvas.detach();
-}
-
-SkCanvas* SkCanvasStateUtils::CreateFromCanvasState(const SkCanvasState* state) {
-    SkASSERT(state);
-
-    // check that the versions match
-    if (CANVAS_STATE_VERSION != state->version) {
-        SkDebugf("CreateFromCanvasState version does not match the one use to create the input");
-        return NULL;
-    }
-
-    if (state->layerCount < 1) {
-        return NULL;
-    }
-
-    SkAutoTUnref<SkNWayCanvas> canvas(SkNEW_ARGS(SkNWayCanvas, (state->width, state->height)));
-
-    // setup the matrix and clip on the n-way canvas
-    setup_canvas_from_MC_state(state->mcState, canvas);
-
-    // Iterate over the layers and add them to the n-way canvas
-    for (int i = 0; i < state->layerCount; ++i) {
-        SkAutoTUnref<SkCanvas> canvasLayer(create_canvas_from_canvas_layer(state->layers[i]));
-        if (!canvasLayer.get()) {
-            return NULL;
-        }
-        canvas->addCanvas(canvasLayer.get());
-    }
-
-    return canvas.detach();
-}
-
-////////////////////////////////////////////////////////////////////////////////
-
-void SkCanvasStateUtils::ReleaseCanvasState(SkCanvasState* state) {
-    SkDELETE(state);
-}