/// <summary>
/// Draw the elements indices.
/// </summary>
/// <param name="ctx">
/// The <see cref="GraphicsContext"/> used for drawing.
/// </param>
protected virtual void DrawElementsInstanced(GraphicsContext ctx, IntPtr pointer, uint instances)
{
uint count = (ElementCount == 0) ? ArrayIndices.ItemCount : ElementCount;
Debug.Assert(count - ElementOffset <= ArrayIndices.ItemCount, "element indices array out of bounds");
// Draw elements
Gl.DrawElementsInstanced(ElementsMode, (int)count, ArrayIndices.ElementsType, pointer, (int)instances);
}
/// <summary>
/// OGL3 method uses a vertex array object for quickly binding the VBOs to their attributes.
/// </summary>
private void DrawInstancedOGL3(int count)
{
if (ID == 0 || VertexCount == 0 || count == 0)
{
return;
}
Gl.BindVertexArray(ID);
Gl.DrawElementsInstanced(DrawMode, VertexCount, elementType, IntPtr.Zero, count);
Gl.BindVertexArray(0);
}