Annotate gd script

Examples/exposure_shader.gd

@@ -12,11 +12,13 @@ func _init():
 	effect_callback_type = EFFECT_CALLBACK_TYPE_POST_TRANSPARENT
 	rd = RenderingServer.get_rendering_device()
 
+	# To make use of an existing ACompute shader we use its filename to access it, in this case, the example compute shader file is 'exposure_example.acompute'
 	exposure_compute = ACompute.new('exposure_example')
 
 
 func _notification(what):
 	if what == NOTIFICATION_PREDELETE:
+		# ACompute will handle the freeing of any resources attached to it
 		exposure_compute.free()
 
 
@@ -44,15 +46,19 @@ func _render_callback(p_effect_callback_type, p_render_data):
 	var y_groups = (size.y - 1) / 8 + 1
 	var z_groups = 1
 	
+	# Vulkan has a feature known as push constants which are like uniform sets but for very small amounts of data
 	var push_constant : PackedFloat32Array = PackedFloat32Array([size.x, size.y, 0.0, 0.0])
 	
 	for view in range(render_scene_buffers.get_view_count()):
 		var input_image = render_scene_buffers.get_color_layer(view)
 
+		# Pack the exposure vector into a byte array
 		var uniform_array = PackedFloat32Array([exposure.x, exposure.y, exposure.z, exposure.w]).to_byte_array()
 
+		# ACompute handles uniform caching under the hood, as long as the exposure value doesn't change or the render target doesn't change, these functions will only do work once
 		exposure_compute.set_texture(0, input_image)
 		exposure_compute.set_uniform_buffer(1, uniform_array)
 		exposure_compute.set_push_constant(push_constant.to_byte_array())
 
+		# Dispatch the compute kernel
 		exposure_compute.dispatch(0, x_groups, y_groups, z_groups)