1 files changed, 322 insertions, 0 deletions
diff --git a/gfx/angle/checkout/src/libANGLE/TransformFeedback.cpp b/gfx/angle/checkout/src/libANGLE/TransformFeedback.cpp
new file mode 100644
index 0000000000..3222f14b8f
--- /dev/null
+++ b/gfx/angle/checkout/src/libANGLE/TransformFeedback.cpp
@@ -0,0 +1,322 @@
+//
+// Copyright (c) 2014 The ANGLE Project 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 "libANGLE/TransformFeedback.h"
+
+#include "common/mathutil.h"
+#include "libANGLE/Buffer.h"
+#include "libANGLE/Caps.h"
+#include "libANGLE/Context.h"
+#include "libANGLE/Program.h"
+#include "libANGLE/State.h"
+#include "libANGLE/renderer/GLImplFactory.h"
+#include "libANGLE/renderer/TransformFeedbackImpl.h"
+
+#include <limits>
+
+namespace gl
+{
+
+angle::CheckedNumeric<GLsizeiptr> GetVerticesNeededForDraw(PrimitiveMode primitiveMode,
+                                                           GLsizei count,
+                                                           GLsizei primcount)
+{
+    if (count < 0 || primcount < 0)
+    {
+        return 0;
+    }
+    // Transform feedback only outputs complete primitives, so we need to round down to the nearest
+    // complete primitive before multiplying by the number of instances.
+    angle::CheckedNumeric<GLsizeiptr> checkedCount     = count;
+    angle::CheckedNumeric<GLsizeiptr> checkedPrimcount = primcount;
+    switch (primitiveMode)
+    {
+        case PrimitiveMode::Triangles:
+            return checkedPrimcount * (checkedCount - checkedCount % 3);
+        case PrimitiveMode::Lines:
+            return checkedPrimcount * (checkedCount - checkedCount % 2);
+        case PrimitiveMode::Points:
+            return checkedPrimcount * checkedCount;
+        default:
+            UNREACHABLE();
+            return checkedPrimcount * checkedCount;
+    }
+}
+
+TransformFeedbackState::TransformFeedbackState(size_t maxIndexedBuffers)
+    : mLabel(),
+      mActive(false),
+      mPrimitiveMode(PrimitiveMode::InvalidEnum),
+      mPaused(false),
+      mVerticesDrawn(0),
+      mVertexCapacity(0),
+      mProgram(nullptr),
+      mIndexedBuffers(maxIndexedBuffers)
+{}
+
+TransformFeedbackState::~TransformFeedbackState() {}
+
+const OffsetBindingPointer<Buffer> &TransformFeedbackState::getIndexedBuffer(size_t idx) const
+{
+    return mIndexedBuffers[idx];
+}
+
+const std::vector<OffsetBindingPointer<Buffer>> &TransformFeedbackState::getIndexedBuffers() const
+{
+    return mIndexedBuffers;
+}
+
+GLsizeiptr TransformFeedbackState::getPrimitivesDrawn() const
+{
+    switch (mPrimitiveMode)
+    {
+        case gl::PrimitiveMode::Points:
+            return mVerticesDrawn;
+        case gl::PrimitiveMode::Lines:
+            return mVerticesDrawn / 2;
+        case gl::PrimitiveMode::Triangles:
+            return mVerticesDrawn / 3;
+        default:
+            return 0;
+    }
+}
+
+TransformFeedback::TransformFeedback(rx::GLImplFactory *implFactory, GLuint id, const Caps &caps)
+    : RefCountObject(id),
+      mState(caps.maxTransformFeedbackSeparateAttributes),
+      mImplementation(implFactory->createTransformFeedback(mState))
+{
+    ASSERT(mImplementation != nullptr);
+}
+
+void TransformFeedback::onDestroy(const Context *context)
+{
+    ASSERT(!context || !context->isCurrentTransformFeedback(this));
+    if (mState.mProgram)
+    {
+        mState.mProgram->release(context);
+        mState.mProgram = nullptr;
+    }
+
+    ASSERT(!mState.mProgram);
+    for (size_t i = 0; i < mState.mIndexedBuffers.size(); i++)
+    {
+        mState.mIndexedBuffers[i].set(context, nullptr, 0, 0);
+    }
+}
+
+TransformFeedback::~TransformFeedback()
+{
+    SafeDelete(mImplementation);
+}
+
+void TransformFeedback::setLabel(const Context *context, const std::string &label)
+{
+    mState.mLabel = label;
+}
+
+const std::string &TransformFeedback::getLabel() const
+{
+    return mState.mLabel;
+}
+
+angle::Result TransformFeedback::begin(const Context *context,
+                                       PrimitiveMode primitiveMode,
+                                       Program *program)
+{
+    ANGLE_TRY(mImplementation->begin(context, primitiveMode));
+    mState.mActive        = true;
+    mState.mPrimitiveMode = primitiveMode;
+    mState.mPaused        = false;
+    mState.mVerticesDrawn = 0;
+    bindProgram(context, program);
+
+    if (program)
+    {
+        // Compute the number of vertices we can draw before overflowing the bound buffers.
+        auto strides = program->getTransformFeedbackStrides();
+        ASSERT(strides.size() <= mState.mIndexedBuffers.size() && !strides.empty());
+        GLsizeiptr minCapacity = std::numeric_limits<GLsizeiptr>::max();
+        for (size_t index = 0; index < strides.size(); index++)
+        {
+            GLsizeiptr capacity =
+                GetBoundBufferAvailableSize(mState.mIndexedBuffers[index]) / strides[index];
+            minCapacity = std::min(minCapacity, capacity);
+        }
+        mState.mVertexCapacity = minCapacity;
+    }
+    else
+    {
+        mState.mVertexCapacity = 0;
+    }
+    return angle::Result::Continue;
+}
+
+angle::Result TransformFeedback::end(const Context *context)
+{
+    ANGLE_TRY(mImplementation->end(context));
+    mState.mActive         = false;
+    mState.mPrimitiveMode  = PrimitiveMode::InvalidEnum;
+    mState.mPaused         = false;
+    mState.mVerticesDrawn  = 0;
+    mState.mVertexCapacity = 0;
+    if (mState.mProgram)
+    {
+        mState.mProgram->release(context);
+        mState.mProgram = nullptr;
+    }
+    return angle::Result::Continue;
+}
+
+angle::Result TransformFeedback::pause(const Context *context)
+{
+    ANGLE_TRY(mImplementation->pause(context));
+    mState.mPaused = true;
+    return angle::Result::Continue;
+}
+
+angle::Result TransformFeedback::resume(const Context *context)
+{
+    ANGLE_TRY(mImplementation->resume(context));
+    mState.mPaused = false;
+    return angle::Result::Continue;
+}
+
+bool TransformFeedback::isPaused() const
+{
+    return mState.mPaused;
+}
+
+PrimitiveMode TransformFeedback::getPrimitiveMode() const
+{
+    return mState.mPrimitiveMode;
+}
+
+bool TransformFeedback::checkBufferSpaceForDraw(GLsizei count, GLsizei primcount) const
+{
+    auto vertices =
+        mState.mVerticesDrawn + GetVerticesNeededForDraw(mState.mPrimitiveMode, count, primcount);
+    return vertices.IsValid() && vertices.ValueOrDie() <= mState.mVertexCapacity;
+}
+
+void TransformFeedback::onVerticesDrawn(const Context *context, GLsizei count, GLsizei primcount)
+{
+    ASSERT(mState.mActive && !mState.mPaused);
+    // All draws should be validated with checkBufferSpaceForDraw so ValueOrDie should never fail.
+    mState.mVerticesDrawn =
+        (mState.mVerticesDrawn + GetVerticesNeededForDraw(mState.mPrimitiveMode, count, primcount))
+            .ValueOrDie();
+
+    for (auto &buffer : mState.mIndexedBuffers)
+    {
+        if (buffer.get() != nullptr)
+        {
+            buffer->onTransformFeedback();
+        }
+    }
+}
+
+void TransformFeedback::bindProgram(const Context *context, Program *program)
+{
+    if (mState.mProgram != program)
+    {
+        if (mState.mProgram != nullptr)
+        {
+            mState.mProgram->release(context);
+        }
+        mState.mProgram = program;
+        if (mState.mProgram != nullptr)
+        {
+            mState.mProgram->addRef();
+        }
+    }
+}
+
+bool TransformFeedback::hasBoundProgram(GLuint program) const
+{
+    return mState.mProgram != nullptr && mState.mProgram->id() == program;
+}
+
+angle::Result TransformFeedback::detachBuffer(const Context *context, GLuint bufferName)
+{
+    bool isBound = context->isCurrentTransformFeedback(this);
+    for (size_t index = 0; index < mState.mIndexedBuffers.size(); index++)
+    {
+        if (mState.mIndexedBuffers[index].id() == bufferName)
+        {
+            if (isBound)
+            {
+                mState.mIndexedBuffers[index]->onTFBindingChanged(context, false, true);
+            }
+            mState.mIndexedBuffers[index].set(context, nullptr, 0, 0);
+            ANGLE_TRY(
+                mImplementation->bindIndexedBuffer(context, index, mState.mIndexedBuffers[index]));
+        }
+    }
+
+    return angle::Result::Continue;
+}
+
+angle::Result TransformFeedback::bindIndexedBuffer(const Context *context,
+                                                   size_t index,
+                                                   Buffer *buffer,
+                                                   size_t offset,
+                                                   size_t size)
+{
+    ASSERT(index < mState.mIndexedBuffers.size());
+    bool isBound = context && context->isCurrentTransformFeedback(this);
+    if (isBound && mState.mIndexedBuffers[index].get())
+    {
+        mState.mIndexedBuffers[index]->onTFBindingChanged(context, false, true);
+    }
+    mState.mIndexedBuffers[index].set(context, buffer, offset, size);
+    if (isBound && buffer)
+    {
+        buffer->onTFBindingChanged(context, true, true);
+    }
+
+    return mImplementation->bindIndexedBuffer(context, index, mState.mIndexedBuffers[index]);
+}
+
+const OffsetBindingPointer<Buffer> &TransformFeedback::getIndexedBuffer(size_t index) const
+{
+    ASSERT(index < mState.mIndexedBuffers.size());
+    return mState.mIndexedBuffers[index];
+}
+
+size_t TransformFeedback::getIndexedBufferCount() const
+{
+    return mState.mIndexedBuffers.size();
+}
+
+bool TransformFeedback::buffersBoundForOtherUse() const
+{
+    for (auto &buffer : mState.mIndexedBuffers)
+    {
+        if (buffer.get() && buffer->isBoundForTransformFeedbackAndOtherUse())
+        {
+            return true;
+        }
+    }
+    return false;
+}
+
+rx::TransformFeedbackImpl *TransformFeedback::getImplementation() const
+{
+    return mImplementation;
+}
+
+void TransformFeedback::onBindingChanged(const Context *context, bool bound)
+{
+    for (auto &buffer : mState.mIndexedBuffers)
+    {
+        if (buffer.get())
+        {
+            buffer->onTFBindingChanged(context, bound, true);
+        }
+    }
+}
+}  // namespace gl