copy method
Implementation
RenderTarget copy(RenderTarget source){
height = source.height;
width = source.width;
depth = source.depth;
scissor.setFrom( source.scissor );
scissorTest = source.scissorTest;
viewport.setFrom( source.viewport );
textures.length = 0;
for (int i = 0, il = source.textures.length; i < il; i ++ ) {
textures.add(source.textures[ i ].clone());
textures[ i ].isRenderTargetTexture = true;
}
// ensure image object is not shared, see #20328
final image = source.texture.image;
texture.source = Source( image );
depthBuffer = source.depthBuffer;
stencilBuffer = source.stencilBuffer;
resolveDepthBuffer = source.resolveDepthBuffer;
resolveStencilBuffer = source.resolveStencilBuffer;
if ( source.depthTexture != null ) depthTexture = source.depthTexture!.clone();
samples = source.samples;
return this;
}