Revert "Revert "Revert "TextureView Vulkan support and optimized OpenGL draw"""

This reverts commit 85f9096b5272c9a39e592e2e97cbbe6cb0e767ab.

Reason for revert: lensblur broken.

Change-Id: I83ac163159fc537bc15936a0f8597a7512ca9d6e
diff --git a/libs/hwui/PixelBuffer.cpp b/libs/hwui/PixelBuffer.cpp
new file mode 100644
index 0000000..910a988
--- /dev/null
+++ b/libs/hwui/PixelBuffer.cpp
@@ -0,0 +1,156 @@
+/*
+ * 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.
+ */
+
+#include "PixelBuffer.h"
+
+#include "Debug.h"
+#include "Extensions.h"
+#include "Properties.h"
+#include "renderstate/RenderState.h"
+#include "utils/GLUtils.h"
+
+#include <utils/Log.h>
+
+namespace android {
+namespace uirenderer {
+
+///////////////////////////////////////////////////////////////////////////////
+// CPU pixel buffer
+///////////////////////////////////////////////////////////////////////////////
+
+class CpuPixelBuffer : public PixelBuffer {
+public:
+    CpuPixelBuffer(GLenum format, uint32_t width, uint32_t height);
+
+    uint8_t* map(AccessMode mode = kAccessMode_ReadWrite) override;
+
+    void upload(uint32_t x, uint32_t y, uint32_t width, uint32_t height, int offset) override;
+
+protected:
+    void unmap() override;
+
+private:
+    std::unique_ptr<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)]) {}
+
+uint8_t* CpuPixelBuffer::map(AccessMode mode) {
+    if (mAccessMode == kAccessMode_None) {
+        mAccessMode = mode;
+    }
+    return mBuffer.get();
+}
+
+void CpuPixelBuffer::unmap() {
+    mAccessMode = kAccessMode_None;
+}
+
+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) override;
+
+    void upload(uint32_t x, uint32_t y, uint32_t width, uint32_t height, int offset) override;
+
+protected:
+    void unmap() override;
+
+private:
+    GLuint mBuffer;
+    uint8_t* mMappedPointer;
+    Caches& mCaches;
+};
+
+GpuPixelBuffer::GpuPixelBuffer(GLenum format, uint32_t width, uint32_t height)
+        : PixelBuffer(format, width, height)
+        , mMappedPointer(nullptr)
+        , mCaches(Caches::getInstance()) {
+    glGenBuffers(1, &mBuffer);
+
+    mCaches.pixelBufferState().bind(mBuffer);
+    glBufferData(GL_PIXEL_UNPACK_BUFFER, getSize(), nullptr, GL_DYNAMIC_DRAW);
+    mCaches.pixelBufferState().unbind();
+}
+
+GpuPixelBuffer::~GpuPixelBuffer() {
+    glDeleteBuffers(1, &mBuffer);
+}
+
+uint8_t* GpuPixelBuffer::map(AccessMode mode) {
+    if (mAccessMode == kAccessMode_None) {
+        mCaches.pixelBufferState().bind(mBuffer);
+        mMappedPointer = (uint8_t*)glMapBufferRange(GL_PIXEL_UNPACK_BUFFER, 0, getSize(), mode);
+        if (CC_UNLIKELY(!mMappedPointer)) {
+            GLUtils::dumpGLErrors();
+            LOG_ALWAYS_FATAL("Failed to map PBO");
+        }
+        mAccessMode = mode;
+        mCaches.pixelBufferState().unbind();
+    }
+
+    return mMappedPointer;
+}
+
+void GpuPixelBuffer::unmap() {
+    if (mAccessMode != kAccessMode_None) {
+        if (mMappedPointer) {
+            mCaches.pixelBufferState().bind(mBuffer);
+            GLboolean status = glUnmapBuffer(GL_PIXEL_UNPACK_BUFFER);
+            if (status == GL_FALSE) {
+                ALOGE("Corrupted GPU pixel buffer");
+            }
+        }
+        mAccessMode = kAccessMode_None;
+        mMappedPointer = nullptr;
+    }
+}
+
+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.pixelBufferState().bind(mBuffer);
+    unmap();
+    glTexSubImage2D(GL_TEXTURE_2D, 0, x, y, width, height, mFormat, GL_UNSIGNED_BYTE,
+                    reinterpret_cast<void*>(offset));
+    mCaches.pixelBufferState().unbind();
+}
+
+///////////////////////////////////////////////////////////////////////////////
+// Factory
+///////////////////////////////////////////////////////////////////////////////
+
+PixelBuffer* PixelBuffer::create(GLenum format, uint32_t width, uint32_t height, BufferType type) {
+    if (type == kBufferType_Auto && Caches::getInstance().gpuPixelBuffersEnabled) {
+        return new GpuPixelBuffer(format, width, height);
+    }
+    return new CpuPixelBuffer(format, width, height);
+}
+
+};  // namespace uirenderer
+};  // namespace android