1 files changed, 117 insertions, 0 deletions
diff --git a/cc/layer_texture_sub_image.cc b/cc/layer_texture_sub_image.cc
new file mode 100644
index 0000000..60f5311
--- /dev/null
+++ b/cc/layer_texture_sub_image.cc
@@ -0,0 +1,117 @@
+// Copyright 2011 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "config.h"
+
+#if USE(ACCELERATED_COMPOSITING)
+
+#include "LayerTextureSubImage.h"
+
+#include "CCRendererGL.h" // For the GLC() macro.
+#include "GraphicsContext3D.h"
+#include "Extensions3DChromium.h"
+#include "TraceEvent.h"
+#include <public/WebGraphicsContext3D.h>
+
+using WebKit::WebGraphicsContext3D;
+
+namespace cc {
+
+LayerTextureSubImage::LayerTextureSubImage(bool useMapTexSubImage)
+    : m_useMapTexSubImage(useMapTexSubImage)
+    , m_subImageSize(0)
+{
+}
+
+LayerTextureSubImage::~LayerTextureSubImage()
+{
+}
+
+void LayerTextureSubImage::upload(const uint8_t* image, const IntRect& imageRect,
+                                  const IntRect& sourceRect, const IntSize& destOffset,
+                                  GC3Denum format, WebGraphicsContext3D* context)
+{
+    if (m_useMapTexSubImage)
+        uploadWithMapTexSubImage(image, imageRect, sourceRect, destOffset, format, context);
+    else
+        uploadWithTexSubImage(image, imageRect, sourceRect, destOffset, format, context);
+}
+
+void LayerTextureSubImage::uploadWithTexSubImage(const uint8_t* image, const IntRect& imageRect,
+                                                 const IntRect& sourceRect, const IntSize& destOffset,
+                                                 GC3Denum format, WebGraphicsContext3D* context)
+{
+    TRACE_EVENT0("cc", "LayerTextureSubImage::uploadWithTexSubImage");
+
+    // Offset from image-rect to source-rect.
+    IntPoint offset(sourceRect.x() - imageRect.x(), sourceRect.y() - imageRect.y());
+
+    const uint8_t* pixelSource;
+    if (imageRect.width() == sourceRect.width() && !offset.x())
+        pixelSource = &image[4 * offset.y() * imageRect.width()];
+    else {
+        size_t neededSize = 4 * sourceRect.width() * sourceRect.height();
+        if (m_subImageSize < neededSize) {
+          m_subImage = adoptArrayPtr(new uint8_t[neededSize]);
+          m_subImageSize = neededSize;
+        }
+        // Strides not equal, so do a row-by-row memcpy from the
+        // paint results into a temp buffer for uploading.
+        for (int row = 0; row < sourceRect.height(); ++row)
+            memcpy(&m_subImage[sourceRect.width() * 4 * row],
+                   &image[4 * (offset.x() + (offset.y() + row) * imageRect.width())],
+                   sourceRect.width() * 4);
+
+        pixelSource = &m_subImage[0];
+    }
+
+    GLC(context, context->texSubImage2D(GraphicsContext3D::TEXTURE_2D, 0, destOffset.width(), destOffset.height(), sourceRect.width(), sourceRect.height(), format, GraphicsContext3D::UNSIGNED_BYTE, pixelSource));
+}
+
+void LayerTextureSubImage::uploadWithMapTexSubImage(const uint8_t* image, const IntRect& imageRect,
+                                                    const IntRect& sourceRect, const IntSize& destOffset,
+                                                    GC3Denum format, WebGraphicsContext3D* context)
+{
+    TRACE_EVENT0("cc", "LayerTextureSubImage::uploadWithMapTexSubImage");
+    // Offset from image-rect to source-rect.
+    IntPoint offset(sourceRect.x() - imageRect.x(), sourceRect.y() - imageRect.y());
+
+    // Upload tile data via a mapped transfer buffer
+    uint8_t* pixelDest = static_cast<uint8_t*>(context->mapTexSubImage2DCHROMIUM(GraphicsContext3D::TEXTURE_2D, 0, destOffset.width(), destOffset.height(), sourceRect.width(), sourceRect.height(), format, GraphicsContext3D::UNSIGNED_BYTE, Extensions3DChromium::WRITE_ONLY));
+
+    if (!pixelDest) {
+        uploadWithTexSubImage(image, imageRect, sourceRect, destOffset, format, context);
+        return;
+    }
+
+    unsigned int componentsPerPixel = 0;
+    switch (format) {
+    case GraphicsContext3D::RGBA:
+    case Extensions3D::BGRA_EXT:
+        componentsPerPixel = 4;
+        break;
+    case GraphicsContext3D::LUMINANCE:
+        componentsPerPixel = 1;
+        break;
+    default:
+        ASSERT_NOT_REACHED();
+    }
+    unsigned int bytesPerComponent = 1;
+
+    if (imageRect.width() == sourceRect.width() && !offset.x())
+        memcpy(pixelDest, &image[offset.y() * imageRect.width() * componentsPerPixel * bytesPerComponent], imageRect.width() * sourceRect.height() * componentsPerPixel * bytesPerComponent);
+    else {
+        // Strides not equal, so do a row-by-row memcpy from the
+        // paint results into the pixelDest
+        for (int row = 0; row < sourceRect.height(); ++row)
+            memcpy(&pixelDest[sourceRect.width() * row * componentsPerPixel * bytesPerComponent],
+                   &image[4 * (offset.x() + (offset.y() + row) * imageRect.width())],
+                   sourceRect.width() * componentsPerPixel * bytesPerComponent);
+    }
+    GLC(context, context->unmapTexSubImage2DCHROMIUM(pixelDest));
+}
+
+} // namespace cc
+
+#endif // USE(ACCELERATED_COMPOSITING)