Texture paint with decay


The current project I’m working on requires that a person in front of a camera can “paint” on a texture, don’t know how to describe it properly (see included patch). I patched something that kinda works, but I was wondering if there is some more efficientway to do something like that, maybe with shaders?



Texture Decay.v4p (20.1 kB)

have a look at this patch:

hm, I probably should have been clearer what I need ;)
that motionblur patch works really nice, but I would need something where the moving “white painter thing” is not always 100% white, but gets whiter the longer you move it over the same spot (in my patch just toggle the reverse of the lfo a few times to see what I mean)

i’d say you can use the motionblur, but draw the stuff in add mode and chage the brightness of the objects, have a look at the Blend (EX9.RenderState) .

hm, I just can’t get it to work the way I want, I guess I’m still too noobish with all that directx renderstate etc stuff :(
Maybe you could patch something up an post it here, if it isn’t too much trouble?

something in this way

draw.v4p (16.8 kB)

thanx for your effort ggml. but in your patch the drawn white areas never fade away.
Again I tried many things with your patch, even a shader, but it never works the way I want it to. oddly, when using the shader (and also the second part of the motionblur patch from tonfilms link) I get the white stuff to decay, but it moves slowly to the right bottom corner of the renderer.

fade away as with queue ?

draw (2).v4p (12.9 kB)

kind of like that, but more “smooth”. just hava a look at the patch I postet when starting this thread, that is the effect I need. thanks again for your help =)

Than perhaps use a Blurr Shader to smooth things out a bit?

Cool patch ggml :) Better than my photoshop plugin ;)

Maybe this will work?
Do note you need more than 8bit in depth for it to fully fade to black. Or else it will be stuck at dark gray.
the / nodes are used to position the texture so it don’t “drift” away due to mismatch between frame coordinates and texture coordinates.
You might want to clear the screen with a black quad when changing size or opening the patch so it don’t leave artifacts.

Paint.v4p (8.5 kB)