Shaders. Little troubles

[o.selyukov]

Hi! Perhaps someone can explain to me where I’m wrong.

1. Changing the opacity
> go.set(“#sprite”, “tint.w”, 0.5)

	or
go.animate("#sprite", "tint.w", go.PLAYBACK_ONCE_FORWARD, 0.5 , go.EASING_OUTSINE, 0.1)

It’s work fine, okay

2. Custom material (any) in render-script

function update(self)
	...
	render.enable_material("my_material")	
	local constants = render.constant_buffer() 
	constants.my_variable = vmath.vector4(...)
	
	render.draw(self.tile_pred, constants)
	
	render.disable_material()
	...
end

And it works too.

But if I use (1) + (2) I get Error:

What am I missing?

Thanks.

[Ragnar_Svensson]

This is most likely a bug in Defold! It is not really designed to use both (1)+(2). (2) is a hostile takeover (designed as such) of the shading by the render script. You are supposed to use the render.constant_buffer to control the constants, rather than controlling them as properties in (1). It should still work without causing an error at all.

[o.selyukov]

Hm, I’ve got it.

Thanks

[o.selyukov]

(don’t want to create new thread)
Perhaps you can help me again )

Imagine that we have the material with user variable (e.g. for camera position)

And in render-script:

...
local constants = render.constant_buffer() 
constants.camera_position = vmath.vector4(self.camera_position.x, self.camera_position.y, 0.0, 0.0)
render.draw(self.tile_pred, constants)
...

As before it’s works. For most devices…

When I tried to test this code on the devices listed below I got strange “error”.

Mediox MID8027 Andoid 2.3
ASUS ZENFONE 4 t001 Andoid 4.4.2

Any component of the camera_position vector has become greater than or equal to 0 and less than 2.
i.e. if a component was -193.7, then it will be equal to 0. And so on.

What could be the reason?

[Ragnar_Svensson]

I have absolutely no idea, especially since it seems dependent on some devices. To debug further, I would remove as much things as possible to narrow it down. I see you have another fragment_constant, what happens if you remove that, are the values still corrupted?

[o.selyukov]

Photo story:

1. Ok, deleted TINT from shader:

3. Shader:

4. Result:
   

   

6. And result (bad quality, but you can see barely red):
   

   

7. Сontinue:
   

   

8. Results as in the (4)

9. Finally:
   
   

   
   
   

And results as in the (6)