1 files changed, 171 insertions, 0 deletions
diff --git a/WebCore/platform/graphics/chromium/TextureManager.cpp b/WebCore/platform/graphics/chromium/TextureManager.cpp
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+++ b/WebCore/platform/graphics/chromium/TextureManager.cpp
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+/*
+ * Copyright (C) 2010, Google Inc. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1.  Redistributions of source code must retain the above copyright
+ *     notice, this list of conditions and the following disclaimer.
+ * 2.  Redistributions in binary form must reproduce the above copyright
+ *     notice, this list of conditions and the following disclaimer in the
+ *     documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY APPLE INC. AND ITS CONTRIBUTORS ``AS IS'' AND ANY
+ * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+ * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR ITS CONTRIBUTORS BE LIABLE FOR ANY
+ * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+ * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+ * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
+ * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+ * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include "config.h"
+
+#if USE(ACCELERATED_COMPOSITING)
+
+#include "TextureManager.h"
+
+#include "LayerRendererChromium.h"
+
+namespace WebCore {
+
+static size_t memoryUseBytes(IntSize size, unsigned textureFormat)
+{
+    // FIXME: This assumes all textures are 4 bytes/pixel, like RGBA.
+    return size.width() * size.height() * 4;
+}
+
+TextureManager::TextureManager(GraphicsContext3D* context, size_t memoryLimitBytes, int maxTextureSize)
+    : m_context(context)
+    , m_memoryLimitBytes(memoryLimitBytes)
+    , m_memoryUseBytes(0)
+    , m_maxTextureSize(maxTextureSize)
+    , m_nextToken(1)
+{
+}
+
+TextureToken TextureManager::getToken()
+{
+    return m_nextToken++;
+}
+
+void TextureManager::releaseToken(TextureToken token)
+{
+    TextureMap::iterator it = m_textures.find(token);
+    if (it != m_textures.end())
+        removeTexture(token, it->second);
+}
+
+bool TextureManager::hasTexture(TextureToken token)
+{
+    if (m_textures.contains(token)) {
+        // If someone asks about a texture put it at the end of the LRU list.
+        m_textureLRUSet.remove(token);
+        m_textureLRUSet.add(token);
+        return true;
+    }
+    return false;
+}
+
+void TextureManager::protectTexture(TextureToken token)
+{
+    ASSERT(hasTexture(token));
+    ASSERT(!m_textures.get(token).isProtected);
+    TextureInfo info = m_textures.take(token);
+    info.isProtected = true;
+    m_textures.add(token, info);
+}
+
+void TextureManager::unprotectTexture(TextureToken token)
+{
+    TextureMap::iterator it = m_textures.find(token);
+    if (it != m_textures.end()) {
+        TextureInfo info = it->second;
+        if (info.isProtected) {
+            info.isProtected = false;
+            m_textures.remove(it);
+            m_textures.add(token, info);
+        }
+    }
+}
+
+bool TextureManager::reduceMemoryToLimit(size_t limit)
+{
+    while (m_memoryUseBytes > limit) {
+        ASSERT(!m_textureLRUSet.isEmpty());
+        bool foundCandidate = false;
+        for (ListHashSet<TextureToken>::iterator lruIt = m_textureLRUSet.begin(); lruIt != m_textureLRUSet.end(); ++lruIt) {
+            TextureToken token = *lruIt;
+            TextureInfo info = m_textures.get(token);
+            if (info.isProtected)
+                continue;
+            removeTexture(token, info);
+            foundCandidate = true;
+            break;
+        }
+        if (!foundCandidate)
+            return false;
+    }
+    return true;
+}
+
+void TextureManager::addTexture(TextureToken token, TextureInfo info)
+{
+    ASSERT(!m_textureLRUSet.contains(token));
+    ASSERT(!m_textures.contains(token));
+    m_memoryUseBytes += memoryUseBytes(info.size, info.format);
+    m_textures.set(token, info);
+    m_textureLRUSet.add(token);
+}
+
+void TextureManager::removeTexture(TextureToken token, TextureInfo info)
+{
+    ASSERT(m_textureLRUSet.contains(token));
+    ASSERT(m_textures.contains(token));
+    m_memoryUseBytes -= memoryUseBytes(info.size, info.format);
+    m_textures.remove(token);
+    ASSERT(m_textureLRUSet.contains(token));
+    m_textureLRUSet.remove(token);
+    GLC(m_context.get(), m_context->deleteTexture(info.textureId));
+}
+
+unsigned TextureManager::requestTexture(TextureToken token, IntSize size, unsigned format, bool* newTexture)
+{
+    if (size.width() > m_maxTextureSize || size.height() > m_maxTextureSize)
+        return 0;
+
+    TextureMap::iterator it = m_textures.find(token);
+    if (it != m_textures.end()) {
+        ASSERT(it->second.size != size || it->second.format != format);
+        removeTexture(token, it->second);
+    }
+
+    size_t memoryRequiredBytes = memoryUseBytes(size, format);
+    if (memoryRequiredBytes > m_memoryLimitBytes || !reduceMemoryToLimit(m_memoryLimitBytes - memoryRequiredBytes))
+        return 0;
+
+    unsigned textureId = m_context->createTexture();
+    GLC(m_context.get(), textureId = m_context->createTexture());
+    GLC(m_context.get(), m_context->bindTexture(GraphicsContext3D::TEXTURE_2D, textureId));
+    // Do basic linear filtering on resize.
+    GLC(m_context.get(), m_context->texParameteri(GraphicsContext3D::TEXTURE_2D, GraphicsContext3D::TEXTURE_MIN_FILTER, GraphicsContext3D::LINEAR));
+    GLC(m_context.get(), m_context->texParameteri(GraphicsContext3D::TEXTURE_2D, GraphicsContext3D::TEXTURE_MAG_FILTER, GraphicsContext3D::LINEAR));
+    // NPOT textures in GL ES only work when the wrap mode is set to GraphicsContext3D::CLAMP_TO_EDGE.
+    GLC(m_context.get(), m_context->texParameteri(GraphicsContext3D::TEXTURE_2D, GraphicsContext3D::TEXTURE_WRAP_S, GraphicsContext3D::CLAMP_TO_EDGE));
+    GLC(m_context.get(), m_context->texParameteri(GraphicsContext3D::TEXTURE_2D, GraphicsContext3D::TEXTURE_WRAP_T, GraphicsContext3D::CLAMP_TO_EDGE));
+    GLC(m_context.get(), m_context->texImage2DResourceSafe(GraphicsContext3D::TEXTURE_2D, 0, format, size.width(), size.height(), 0, format, GraphicsContext3D::UNSIGNED_BYTE));
+    TextureInfo info;
+    info.size = size;
+    info.format = format;
+    info.textureId = textureId;
+    info.isProtected = true;
+    addTexture(token, info);
+    return textureId;
+}
+
+}
+
+#endif // USE(ACCELERATED_COMPOSITING)