Recycle OffscreenBuffers
Change-Id: Ia2e219026f211a5308ecf8209c5f986bb888aadd
diff --git a/libs/hwui/renderstate/OffscreenBufferPool.cpp b/libs/hwui/renderstate/OffscreenBufferPool.cpp
new file mode 100644
index 0000000..6b44557
--- /dev/null
+++ b/libs/hwui/renderstate/OffscreenBufferPool.cpp
@@ -0,0 +1,196 @@
+/*
+ * Copyright (C) 2015 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include "OffscreenBufferPool.h"
+
+#include "Caches.h"
+#include "Properties.h"
+#include "renderstate/RenderState.h"
+#include "utils/FatVector.h"
+
+#include <utils/Log.h>
+
+#include <GLES2/gl2.h>
+
+namespace android {
+namespace uirenderer {
+
+////////////////////////////////////////////////////////////////////////////////
+// OffscreenBuffer
+////////////////////////////////////////////////////////////////////////////////
+
+OffscreenBuffer::OffscreenBuffer(RenderState& renderState, Caches& caches,
+ uint32_t viewportWidth, uint32_t viewportHeight)
+ : renderState(renderState)
+ , viewportWidth(viewportWidth)
+ , viewportHeight(viewportHeight)
+ , texture(caches) {
+ texture.width = computeIdealDimension(viewportWidth);
+ texture.height = computeIdealDimension(viewportHeight);
+ texture.blend = true;
+
+ caches.textureState().activateTexture(0);
+ glGenTextures(1, &texture.id);
+ caches.textureState().bindTexture(GL_TEXTURE_2D, texture.id);
+
+ texture.setWrap(GL_CLAMP_TO_EDGE, false, false, GL_TEXTURE_2D);
+ // not setting filter on texture, since it's set when drawing, based on transform
+
+ glPixelStorei(GL_UNPACK_ALIGNMENT, 4);
+ glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, texture.width, texture.height, 0,
+ GL_RGBA, GL_UNSIGNED_BYTE, nullptr);
+}
+
+void OffscreenBuffer::updateMeshFromRegion() {
+ // avoid T-junctions as they cause artifacts in between the resultant
+ // geometry when complex transforms occur.
+ // TODO: generate the safeRegion only if necessary based on drawing transform
+ Region safeRegion = Region::createTJunctionFreeRegion(region);
+
+ size_t count;
+ const android::Rect* rects = safeRegion.getArray(&count);
+
+ const float texX = 1.0f / float(texture.width);
+ const float texY = 1.0f / float(texture.height);
+
+ FatVector<TextureVertex, 64> meshVector(count * 4); // uses heap if more than 64 vertices needed
+ TextureVertex* mesh = &meshVector[0];
+ for (size_t i = 0; i < count; i++) {
+ const android::Rect* r = &rects[i];
+
+ const float u1 = r->left * texX;
+ const float v1 = (viewportHeight - r->top) * texY;
+ const float u2 = r->right * texX;
+ const float v2 = (viewportHeight - r->bottom) * texY;
+
+ TextureVertex::set(mesh++, r->left, r->top, u1, v1);
+ TextureVertex::set(mesh++, r->right, r->top, u2, v1);
+ TextureVertex::set(mesh++, r->left, r->bottom, u1, v2);
+ TextureVertex::set(mesh++, r->right, r->bottom, u2, v2);
+ }
+ elementCount = count * 6;
+ renderState.meshState().genOrUpdateMeshBuffer(&vbo,
+ sizeof(TextureVertex) * count * 4,
+ &meshVector[0],
+ GL_DYNAMIC_DRAW); // TODO: GL_STATIC_DRAW if savelayer
+}
+
+uint32_t OffscreenBuffer::computeIdealDimension(uint32_t dimension) {
+ return uint32_t(ceilf(dimension / float(LAYER_SIZE)) * LAYER_SIZE);
+}
+
+OffscreenBuffer::~OffscreenBuffer() {
+ texture.deleteTexture();
+ renderState.meshState().deleteMeshBuffer(vbo);
+ elementCount = 0;
+ vbo = 0;
+}
+
+///////////////////////////////////////////////////////////////////////////////
+// OffscreenBufferPool
+///////////////////////////////////////////////////////////////////////////////
+
+OffscreenBufferPool::OffscreenBufferPool()
+ : mMaxSize(Properties::layerPoolSize) {
+}
+
+OffscreenBufferPool::~OffscreenBufferPool() {
+ clear(); // TODO: unique_ptr?
+}
+
+int OffscreenBufferPool::Entry::compare(const Entry& lhs, const Entry& rhs) {
+ int deltaInt = int(lhs.width) - int(rhs.width);
+ if (deltaInt != 0) return deltaInt;
+
+ return int(lhs.height) - int(rhs.height);
+}
+
+void OffscreenBufferPool::clear() {
+ for (auto entry : mPool) {
+ delete entry.layer;
+ }
+ mPool.clear();
+ mSize = 0;
+}
+
+OffscreenBuffer* OffscreenBufferPool::get(RenderState& renderState,
+ const uint32_t width, const uint32_t height) {
+ OffscreenBuffer* layer = nullptr;
+
+ Entry entry(width, height);
+ auto iter = mPool.find(entry);
+
+ if (iter != mPool.end()) {
+ entry = *iter;
+ mPool.erase(iter);
+
+ layer = entry.layer;
+ layer->viewportWidth = width;
+ layer->viewportHeight = height;
+ mSize -= layer->getSizeInBytes();
+ } else {
+ layer = new OffscreenBuffer(renderState, Caches::getInstance(), width, height);
+ }
+
+ return layer;
+}
+
+OffscreenBuffer* OffscreenBufferPool::resize(OffscreenBuffer* layer,
+ const uint32_t width, const uint32_t height) {
+ RenderState& renderState = layer->renderState;
+ if (layer->texture.width == OffscreenBuffer::computeIdealDimension(width)
+ && layer->texture.height == OffscreenBuffer::computeIdealDimension(height)) {
+ // resize in place
+ layer->viewportWidth = width;
+ layer->viewportHeight = height;
+ return layer;
+ }
+ putOrDelete(layer);
+ return get(renderState, width, height);
+}
+
+void OffscreenBufferPool::dump() {
+ for (auto entry : mPool) {
+ ALOGD(" Layer size %dx%d", entry.width, entry.height);
+ }
+}
+
+void OffscreenBufferPool::putOrDelete(OffscreenBuffer* layer) {
+ const uint32_t size = layer->getSizeInBytes();
+ // Don't even try to cache a layer that's bigger than the cache
+ if (size < mMaxSize) {
+ // TODO: Use an LRU
+ while (mSize + size > mMaxSize) {
+ OffscreenBuffer* victim = mPool.begin()->layer;
+ mSize -= victim->getSizeInBytes();
+ delete victim;
+ mPool.erase(mPool.begin());
+ }
+
+ // clear region, since it's no longer valid
+ layer->region.clear();
+
+ Entry entry(layer);
+
+ mPool.insert(entry);
+ mSize += size;
+ } else {
+ delete layer;
+ }
+}
+
+}; // namespace uirenderer
+}; // namespace android