public static void RSSetScissorRects(this ID3D11DeviceContext context, tagRECT[] rects)
{
if (context == null)
{
throw new ArgumentNullException(nameof(context));
}
if (rects == null)
{
throw new ArgumentNullException(nameof(rects));
}
if (rects.Length == 0)
{
throw new ArgumentException(null, nameof(rects));
}
context.RSSetScissorRects(rects.Length, rects);
}
public void Render(ImDrawDataPtr data)
{
// Avoid rendering when minimized
if (data.DisplaySize.X <= 0.0f || data.DisplaySize.Y <= 0.0f)
{
return;
}
ID3D11DeviceContext ctx = deviceContext;
if (vertexBuffer == null || vertexBufferSize < data.TotalVtxCount)
{
vertexBuffer?.Release();
vertexBufferSize = data.TotalVtxCount + 5000;
BufferDescription desc = new BufferDescription();
desc.Usage = Vortice.Direct3D11.Usage.Dynamic;
desc.SizeInBytes = vertexBufferSize * sizeof(ImDrawVert);
desc.BindFlags = BindFlags.VertexBuffer;
desc.CpuAccessFlags = CpuAccessFlags.Write;
vertexBuffer = device.CreateBuffer(desc);
}
if (indexBuffer == null || indexBufferSize < data.TotalIdxCount)
{
indexBuffer?.Release();
indexBufferSize = data.TotalIdxCount + 10000;
BufferDescription desc = new BufferDescription();
desc.Usage = Vortice.Direct3D11.Usage.Dynamic;
desc.SizeInBytes = indexBufferSize * sizeof(ImDrawIdx);
desc.BindFlags = BindFlags.IndexBuffer;
desc.CpuAccessFlags = CpuAccessFlags.Write;
indexBuffer = device.CreateBuffer(desc);
}
// Upload vertex/index data into a single contiguous GPU buffer
var vertexResource = ctx.Map(vertexBuffer, 0, MapMode.WriteDiscard, Vortice.Direct3D11.MapFlags.None);
var indexResource = ctx.Map(indexBuffer, 0, MapMode.WriteDiscard, Vortice.Direct3D11.MapFlags.None);
var vertexResourcePointer = (ImDrawVert *)vertexResource.DataPointer;
var indexResourcePointer = (ImDrawIdx *)indexResource.DataPointer;
for (int n = 0; n < data.CmdListsCount; n++)
{
var cmdlList = data.CmdListsRange[n];
var vertBytes = cmdlList.VtxBuffer.Size * sizeof(ImDrawVert);
Buffer.MemoryCopy((void *)cmdlList.VtxBuffer.Data, vertexResourcePointer, vertBytes, vertBytes);
var idxBytes = cmdlList.IdxBuffer.Size * sizeof(ImDrawIdx);
Buffer.MemoryCopy((void *)cmdlList.IdxBuffer.Data, indexResourcePointer, idxBytes, idxBytes);
vertexResourcePointer += cmdlList.VtxBuffer.Size;
indexResourcePointer += cmdlList.IdxBuffer.Size;
}
ctx.Unmap(vertexBuffer, 0);
ctx.Unmap(indexBuffer, 0);
// Setup orthographic projection matrix into our constant buffer
// Our visible imgui space lies from draw_data.DisplayPos (top left) to draw_data.DisplayPos+data_data.DisplaySize (bottom right). DisplayPos is (0,0) for single viewport apps.
var constResource = ctx.Map(constantBuffer, 0, MapMode.WriteDiscard, Vortice.Direct3D11.MapFlags.None);
var span = constResource.AsSpan <float>(VertexConstantBufferSize);
float L = data.DisplayPos.X;
float R = data.DisplayPos.X + data.DisplaySize.X;
float T = data.DisplayPos.Y;
float B = data.DisplayPos.Y + data.DisplaySize.Y;
float[] mvp =
{
2.0f / (R - L), 0.0f, 0.0f, 0.0f,
0.0f, 2.0f / (T - B), 0.0f, 0.0f,
0.0f, 0.0f, 0.5f, 0.0f,
(R + L) / (L - R), (T + B) / (B - T), 0.5f, 1.0f,
};
mvp.CopyTo(span);
ctx.Unmap(constantBuffer, 0);
SetupRenderState(data, ctx);
// Render command lists
// (Because we merged all buffers into a single one, we maintain our own offset into them)
int global_idx_offset = 0;
int global_vtx_offset = 0;
Vector2 clip_off = data.DisplayPos;
for (int n = 0; n < data.CmdListsCount; n++)
{
var cmdList = data.CmdListsRange[n];
for (int i = 0; i < cmdList.CmdBuffer.Size; i++)
{
var cmd = cmdList.CmdBuffer[i];
if (cmd.UserCallback != IntPtr.Zero)
{
throw new NotImplementedException("user callbacks not implemented");
}
else
{
var rect = new Rect((int)(cmd.ClipRect.X - clip_off.X), (int)(cmd.ClipRect.Y - clip_off.Y), (int)(cmd.ClipRect.Z - clip_off.X), (int)(cmd.ClipRect.W - clip_off.Y));
ctx.RSSetScissorRects(rect);
textureResources.TryGetValue(cmd.TextureId, out var texture);
if (texture != null)
{
ctx.PSSetShaderResources(0, texture);
}
ctx.DrawIndexed((int)cmd.ElemCount, (int)(cmd.IdxOffset + global_idx_offset), (int)(cmd.VtxOffset + global_vtx_offset));
}
}
global_idx_offset += cmdList.IdxBuffer.Size;
global_vtx_offset += cmdList.VtxBuffer.Size;
}
}
