Introduce PixelBuffer API to enable PBOs
PBOs (Pixel Buffer Objects) can be used on OpenGL ES 3.0 to perform
asynchronous texture uploads to free up the CPU. This change does not
enable the use of PBOs unless a specific property is set (Adreno drivers
have issues with PBOs at the moment, Mali drivers work just fine.)
This change also cleans up Font/FontRenderer a little bit and improves
performance of drop shadows generations by using memcpy() instead of
a manual byte-by-byte copy.
On GL ES 2.0 devices, or when PBOs are disabled, a PixelBuffer instance
behaves like a simple byte array. The extra APIs introduced for PBOs
(map/unmap and bind/unbind) are pretty much no-ops for CPU pixel
buffers and won't introduce any significant overhead.
This change also fixes a bug with text drop shadows: if the drop
shadow is larger than the max texture size, the renderer would leave
the GL context in a bad state and generate 0x501 errors. This change
simply skips drop shadows if they are too large.
Change-Id: I2700aadb0c6093431dc5dee3d587d689190c4e23
diff --git a/libs/hwui/PixelBuffer.cpp b/libs/hwui/PixelBuffer.cpp
new file mode 100644
index 0000000..8280370
--- /dev/null
+++ b/libs/hwui/PixelBuffer.cpp
@@ -0,0 +1,163 @@
+/*
+ * Copyright (C) 2013 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.
+ */
+
+#define LOG_TAG "OpenGLRenderer"
+
+#include <utils/Log.h>
+
+#include "Caches.h"
+#include "Extensions.h"
+#include "PixelBuffer.h"
+#include "Properties.h"
+
+namespace android {
+namespace uirenderer {
+
+///////////////////////////////////////////////////////////////////////////////
+// CPU pixel buffer
+///////////////////////////////////////////////////////////////////////////////
+
+class CpuPixelBuffer: public PixelBuffer {
+public:
+ CpuPixelBuffer(GLenum format, uint32_t width, uint32_t height);
+ ~CpuPixelBuffer();
+
+ uint8_t* map(AccessMode mode = kAccessMode_ReadWrite);
+ void unmap();
+
+ uint8_t* getMappedPointer() const;
+
+ void upload(uint32_t x, uint32_t y, uint32_t width, uint32_t height, int offset);
+
+private:
+ uint8_t* mBuffer;
+};
+
+CpuPixelBuffer::CpuPixelBuffer(GLenum format, uint32_t width, uint32_t height):
+ PixelBuffer(format, width, height) {
+ mBuffer = new uint8_t[width * height * formatSize(format)];
+}
+
+CpuPixelBuffer::~CpuPixelBuffer() {
+ delete[] mBuffer;
+}
+
+uint8_t* CpuPixelBuffer::map(AccessMode mode) {
+ if (mAccessMode == kAccessMode_None) {
+ mAccessMode = mode;
+ }
+ return mBuffer;
+}
+
+void CpuPixelBuffer::unmap() {
+ mAccessMode = kAccessMode_None;
+}
+
+uint8_t* CpuPixelBuffer::getMappedPointer() const {
+ return mAccessMode == kAccessMode_None ? NULL : mBuffer;
+}
+
+void CpuPixelBuffer::upload(uint32_t x, uint32_t y, uint32_t width, uint32_t height, int offset) {
+ glTexSubImage2D(GL_TEXTURE_2D, 0, x, y, width, height,
+ mFormat, GL_UNSIGNED_BYTE, mBuffer + offset);
+}
+
+///////////////////////////////////////////////////////////////////////////////
+// GPU pixel buffer
+///////////////////////////////////////////////////////////////////////////////
+
+class GpuPixelBuffer: public PixelBuffer {
+public:
+ GpuPixelBuffer(GLenum format, uint32_t width, uint32_t height);
+ ~GpuPixelBuffer();
+
+ uint8_t* map(AccessMode mode = kAccessMode_ReadWrite);
+ void unmap();
+
+ uint8_t* getMappedPointer() const;
+
+ void upload(uint32_t x, uint32_t y, uint32_t width, uint32_t height, int offset);
+
+private:
+ GLuint mBuffer;
+ uint8_t* mMappedPointer;
+ Caches& mCaches;
+};
+
+GpuPixelBuffer::GpuPixelBuffer(GLenum format, uint32_t width, uint32_t height):
+ PixelBuffer(format, width, height), mMappedPointer(0), mCaches(Caches::getInstance()) {
+ glGenBuffers(1, &mBuffer);
+ mCaches.bindPixelBuffer(mBuffer);
+ glBufferData(GL_PIXEL_UNPACK_BUFFER, getSize(), NULL, GL_DYNAMIC_DRAW);
+ mCaches.unbindPixelBuffer();
+}
+
+GpuPixelBuffer::~GpuPixelBuffer() {
+ glDeleteBuffers(1, &mBuffer);
+}
+
+uint8_t* GpuPixelBuffer::map(AccessMode mode) {
+ if (mAccessMode == kAccessMode_None) {
+ mCaches.bindPixelBuffer(mBuffer);
+ mMappedPointer = (uint8_t*) glMapBufferRange(GL_PIXEL_UNPACK_BUFFER, 0, getSize(), mode);
+ mAccessMode = mode;
+ }
+
+ return mMappedPointer;
+}
+
+void GpuPixelBuffer::unmap() {
+ if (mAccessMode != kAccessMode_None) {
+ if (mMappedPointer) {
+ mCaches.bindPixelBuffer(mBuffer);
+ glUnmapBuffer(GL_PIXEL_UNPACK_BUFFER);
+ }
+ mAccessMode = kAccessMode_None;
+ mMappedPointer = NULL;
+ }
+}
+
+uint8_t* GpuPixelBuffer::getMappedPointer() const {
+ return mMappedPointer;
+}
+
+void GpuPixelBuffer::upload(uint32_t x, uint32_t y, uint32_t width, uint32_t height, int offset) {
+ // If the buffer is not mapped, unmap() will not bind it
+ mCaches.bindPixelBuffer(mBuffer);
+ unmap();
+ glTexSubImage2D(GL_TEXTURE_2D, 0, x, y, width, height, mFormat,
+ GL_UNSIGNED_BYTE, (void*) offset);
+}
+
+///////////////////////////////////////////////////////////////////////////////
+// Factory
+///////////////////////////////////////////////////////////////////////////////
+
+PixelBuffer* PixelBuffer::create(GLenum format, uint32_t width, uint32_t height, BufferType type) {
+ bool gpuBuffer = type == kBufferType_Auto && Extensions::getInstance().getMajorGlVersion() >= 3;
+ if (gpuBuffer) {
+ char property[PROPERTY_VALUE_MAX];
+ if (property_get(PROPERTY_ENABLE_GPU_PIXEL_BUFFERS, property, "false") > 0) {
+ if (!strcmp(property, "true")) {
+ return new GpuPixelBuffer(format, width, height);
+ }
+ }
+ }
+ return new CpuPixelBuffer(format, width, height);
+}
+
+}; // namespace uirenderer
+}; // namespace android