void FTesselatedScreenRectangleIndexBuffer::InitRHI()
{
TResourceArray<uint16, INDEXBUFFER_ALIGNMENT> IndexBuffer;
uint32 NumIndices = NumPrimitives() * 3;
IndexBuffer.AddUninitialized(NumIndices);
uint16* Out = (uint16*)IndexBuffer.GetData();
for(uint32 y = 0; y < Height; ++y)
{
for(uint32 x = 0; x < Width; ++x)
{
// left top to bottom right in reading order
uint16 Index00 = x + y * (Width + 1);
uint16 Index10 = Index00 + 1;
uint16 Index01 = Index00 + (Width + 1);
uint16 Index11 = Index01 + 1;
// todo: diagonal can be flipped on parts of the screen
// triangle A
*Out++ = Index00; *Out++ = Index01; *Out++ = Index10;
// triangle B
*Out++ = Index11; *Out++ = Index10; *Out++ = Index01;
}
}
// Create index buffer. Fill buffer with initial data upon creation
FRHIResourceCreateInfo CreateInfo(&IndexBuffer);
IndexBufferRHI = RHICreateIndexBuffer(sizeof(uint16), IndexBuffer.GetResourceDataSize(), BUF_Static, CreateInfo);
}
/** Initialize the RHI for this rendering resource */
void InitRHI() override
{
// Indices 0 - 5 are used for rendering a quad. Indices 6 - 8 are used for triangle optimization.
const uint16 Indices[] = { 0, 1, 2, 2, 1, 3, 0, 4, 5 };
TResourceArray<uint16, INDEXBUFFER_ALIGNMENT> IndexBuffer;
uint32 InternalNumIndices = ARRAY_COUNT(Indices);
IndexBuffer.AddUninitialized(InternalNumIndices);
FMemory::Memcpy(IndexBuffer.GetData(), Indices, InternalNumIndices * sizeof(uint16));
// Create index buffer. Fill buffer with initial data upon creation
FRHIResourceCreateInfo CreateInfo(&IndexBuffer);
IndexBufferRHI = RHICreateIndexBuffer(sizeof(uint16), IndexBuffer.GetResourceDataSize(), BUF_Static, CreateInfo);
}
/**
* Initialize the RHI for this rendering resource
*/
void InitRHI() override
{
TResourceArray<uint16, INDEXBUFFER_ALIGNMENT> Indices;
NumIndices = ARRAY_COUNT(GCubeIndices);
Indices.AddUninitialized(NumIndices);
FMemory::Memcpy(Indices.GetData(), GCubeIndices, NumIndices * sizeof(uint16));
const uint32 Size = Indices.GetResourceDataSize();
const uint32 Stride = sizeof(uint16);
// Create index buffer. Fill buffer with initial data upon creation
FRHIResourceCreateInfo CreateInfo(&Indices);
IndexBufferRHI = RHICreateIndexBuffer(Stride, Size, BUF_Static, CreateInfo);
}