I'm noob to webgl. After reading the tutorials at webglfundamentals.org and "Introduction to Computer Graphics", i'm able to succesfully draw some stuff and the depth buffer without thirty-party libraries.
Now, i try to go a step further and apply some visual enhancement to my drawings, by usharp-masking the depth buffer, also called "the cheap SSAO".
What i understand is, that i should:
- draw the depth buffer
- blur X
- blur Y
- combine the blurred depth buffer with the diffuse component of the initial image
What i learned so far is, that to apply these four steps, i could use two textures, ping-pong back the textures, apply the effects in sequence to the textures and at the end draw to the screen the final result.
It would be easier with a gl.RGB4 color attachment?
It seems to me, that the final effect is just only to dim the diffuse color of the initial image, so i could draw the depth buffer to the red channel, blur-X the red channel to the green channel, blur-Y the green channel to the blue channel, and then combine this last with the initial drawing.
Isn't this faster or memory-cheaper than swapping two textures, for example by thinking mobile-first?
What are the drawbacks? Anyone already tried this? Thanks in advance