public unsafe RenderTarget CreateRenderTarget(int w, int h)
{
//create a texture for it
int texid = GenTexture();
Texture2d tex = new Texture2d(this, texid, w, h);
GL.BindTexture(TextureTarget.Texture2D, texid);
GL.TexImage2D(TextureTarget.Texture2D, 0, PixelInternalFormat.Rgba8, w, h, 0, PixelFormat.Bgra, PixelType.UnsignedByte, IntPtr.Zero);
tex.SetMagFilter(TextureMagFilter.Nearest);
tex.SetMinFilter(TextureMinFilter.Nearest);
//create the FBO
int fbid = GL.Ext.GenFramebuffer();
GL.Ext.BindFramebuffer(FramebufferTarget.Framebuffer, fbid);
//bind the tex to the FBO
GL.Ext.FramebufferTexture2D(FramebufferTarget.Framebuffer, FramebufferAttachment.ColorAttachment0, TextureTarget.Texture2D, texid, 0);
//do something, I guess say which colorbuffers are used by the framebuffer
DrawBuffersEnum *buffers = stackalloc DrawBuffersEnum[1];
buffers[0] = DrawBuffersEnum.ColorAttachment0;
GL.DrawBuffers(1, buffers);
if (GL.Ext.CheckFramebufferStatus(FramebufferTarget.Framebuffer) != FramebufferErrorCode.FramebufferComplete)
{
throw new InvalidOperationException("Error creating framebuffer (at CheckFramebufferStatus)");
}
//since we're done configuring unbind this framebuffer, to return to the default
GL.Ext.BindFramebuffer(FramebufferTarget.Framebuffer, 0);
return(new RenderTarget(this, fbid, tex));
}
public static void glDrawBuffers(uint n, DrawBuffersEnum *bufs) => p_glDrawBuffers(n, bufs);
