Implemented DX11 GL_TRIANGLE_FAN emulation, using a scratch index buffer.
TRAC #22345
Signed-off-by: Nicolas Capens
Signed-off-by: Daniel Koch
Author: Jamie Madill
git-svn-id: https://angleproject.googlecode.com/svn/branches/dx11proto@1708 736b8ea6-26fd-11df-bfd4-992fa37f6226
diff --git a/src/libGLESv2/renderer/Renderer11.cpp b/src/libGLESv2/renderer/Renderer11.cpp
index 9e71cb7..e82edb2 100644
--- a/src/libGLESv2/renderer/Renderer11.cpp
+++ b/src/libGLESv2/renderer/Renderer11.cpp
@@ -47,6 +47,7 @@
mIndexDataManager = NULL;
mLineLoopIB = NULL;
+ mTriangleFanIB = NULL;
mD3d11Module = NULL;
mDxgiModule = NULL;
@@ -558,7 +559,8 @@
case GL_LINE_STRIP: primitiveTopology = D3D_PRIMITIVE_TOPOLOGY_LINESTRIP; break;
case GL_TRIANGLES: primitiveTopology = D3D_PRIMITIVE_TOPOLOGY_TRIANGLELIST; break;
case GL_TRIANGLE_STRIP: primitiveTopology = D3D_PRIMITIVE_TOPOLOGY_TRIANGLESTRIP; break;
- case GL_TRIANGLE_FAN: UNIMPLEMENTED(); /* TODO */ break;
+ // emulate fans via rewriting index buffer
+ case GL_TRIANGLE_FAN: primitiveTopology = D3D_PRIMITIVE_TOPOLOGY_TRIANGLELIST; break;
default:
return error(GL_INVALID_ENUM, false);
}
@@ -758,6 +760,10 @@
{
drawLineLoop(count, GL_NONE, NULL, 0, NULL);
}
+ else if (mode == GL_TRIANGLE_FAN)
+ {
+ drawTriangleFan(count, GL_NONE, NULL, 0, NULL);
+ }
else if (instances > 0)
{
// TODO
@@ -775,6 +781,10 @@
{
drawLineLoop(count, type, indices, indexInfo.minIndex, elementArrayBuffer);
}
+ else if (mode == GL_TRIANGLE_FAN)
+ {
+ drawTriangleFan(count, type, indices, indexInfo.minIndex, elementArrayBuffer);
+ }
else
{
mDeviceContext->DrawIndexed(count, 0, -static_cast<int>(indexInfo.minIndex));
@@ -873,6 +883,103 @@
mDeviceContext->DrawIndexed(count + 1, 0, -minIndex);
}
+void Renderer11::drawTriangleFan(GLsizei count, GLenum type, const GLvoid *indices, int minIndex, gl::Buffer *elementArrayBuffer)
+{
+ // Get the raw indices for an indexed draw
+ if (type != GL_NONE && elementArrayBuffer)
+ {
+ gl::Buffer *indexBuffer = elementArrayBuffer;
+ intptr_t offset = reinterpret_cast<intptr_t>(indices);
+ indices = static_cast<const GLubyte*>(indexBuffer->data()) + offset;
+ }
+
+ if (!mTriangleFanIB)
+ {
+ mTriangleFanIB = new StreamingIndexBufferInterface(this);
+ if (!mTriangleFanIB->reserveBufferSpace(INITIAL_INDEX_BUFFER_SIZE, GL_UNSIGNED_INT))
+ {
+ delete mTriangleFanIB;
+ mTriangleFanIB = NULL;
+
+ ERR("Could not create a scratch index buffer for GL_TRIANGLE_FAN.");
+ return error(GL_OUT_OF_MEMORY);
+ }
+ }
+
+ const int numTris = count - 2;
+ const int spaceNeeded = (numTris * 3) * sizeof(unsigned int);
+ if (!mTriangleFanIB->reserveBufferSpace(spaceNeeded, GL_UNSIGNED_INT))
+ {
+ ERR("Could not reserve enough space in scratch index buffer for GL_TRIANGLE_FAN.");
+ return error(GL_OUT_OF_MEMORY);
+ }
+
+ void* mappedMemory = NULL;
+ int offset = mTriangleFanIB->mapBuffer(spaceNeeded, &mappedMemory);
+ if (offset == -1 || mappedMemory == NULL)
+ {
+ ERR("Could not map scratch index buffer for GL_TRIANGLE_FAN.");
+ return error(GL_OUT_OF_MEMORY);
+ }
+
+ unsigned int *data = reinterpret_cast<unsigned int*>(mappedMemory);
+ unsigned int indexBufferOffset = static_cast<unsigned int>(offset);
+
+ switch (type)
+ {
+ case GL_NONE: // Non-indexed draw
+ for (int i = 0; i < numTris; i++)
+ {
+ data[i*3 + 0] = 0;
+ data[i*3 + 1] = i + 1;
+ data[i*3 + 2] = i + 2;
+ }
+ break;
+ case GL_UNSIGNED_BYTE:
+ for (int i = 0; i < numTris; i++)
+ {
+ data[i*3 + 0] = static_cast<const GLubyte*>(indices)[0];
+ data[i*3 + 1] = static_cast<const GLubyte*>(indices)[i + 1];
+ data[i*3 + 2] = static_cast<const GLubyte*>(indices)[i + 2];
+ }
+ break;
+ case GL_UNSIGNED_SHORT:
+ for (int i = 0; i < numTris; i++)
+ {
+ data[i*3 + 0] = static_cast<const GLushort*>(indices)[0];
+ data[i*3 + 1] = static_cast<const GLushort*>(indices)[i + 1];
+ data[i*3 + 2] = static_cast<const GLushort*>(indices)[i + 2];
+ }
+ break;
+ case GL_UNSIGNED_INT:
+ for (int i = 0; i < numTris; i++)
+ {
+ data[i*3 + 0] = static_cast<const GLuint*>(indices)[0];
+ data[i*3 + 1] = static_cast<const GLuint*>(indices)[i + 1];
+ data[i*3 + 2] = static_cast<const GLuint*>(indices)[i + 2];
+ }
+ break;
+ default: UNREACHABLE();
+ }
+
+ if (!mTriangleFanIB->unmapBuffer())
+ {
+ ERR("Could not unmap scratch index buffer for GL_TRIANGLE_FAN.");
+ return error(GL_OUT_OF_MEMORY);
+ }
+
+ if (mAppliedIBSerial != mTriangleFanIB->getSerial() || mAppliedIBOffset != indexBufferOffset)
+ {
+ IndexBuffer11 *indexBuffer = IndexBuffer11::makeIndexBuffer11(mTriangleFanIB->getIndexBuffer());
+
+ mDeviceContext->IASetIndexBuffer(indexBuffer->getBuffer(), indexBuffer->getIndexFormat(), indexBufferOffset);
+ mAppliedIBSerial = mTriangleFanIB->getSerial();
+ mAppliedIBOffset = indexBufferOffset;
+ }
+
+ mDeviceContext->DrawIndexed(numTris * 3, 0, -minIndex);
+}
+
void Renderer11::applyShaders(gl::ProgramBinary *programBinary)
{
unsigned int programBinarySerial = programBinary->getSerial();
@@ -1208,6 +1315,9 @@
delete mLineLoopIB;
mLineLoopIB = NULL;
+
+ delete mTriangleFanIB;
+ mTriangleFanIB = NULL;
}
void Renderer11::markDeviceLost()