Processing 1.0 - Processing Discourse - Texture fading to transparancy

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Index › Programming Questions & Help › Programs › Texture fading to transparancy

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Texture fading to transparancy (Read 493 times)

John_Doe

Texture fading to transparancy
Apr 22^nd, 2008, 4:03pm

Hey guys,
is there any way to achieve an effect of fading a polygons texture to complete tranparancy?
During runtime I create a PImage and then gradually add more transparancy to each row of pixels like this:
Quote:

int b = 0;
for (int i = 0; i < copyOfImage.pixels.length; i++) {
int currR = (image.pixels[i] >> 16) & 0xFF;
int currG = (image.pixels[i] >> 8) & 0xFF;
int currB = image.pixels[i] & 0xFF;

if (i%image.width == 0)
b++;

copyOfImage.pixels[copyOfImage.pixels.length -i -1] = pa.color(currR, currG, currB, b * 2);
}

This works when I display the image with the 'image()' function. But this only allows me to draw it at Z=0 (right?)

Thus I set the image as a texture of a polygon but then the gradual alpha effect is lost and it seems that only the whole texture can be set to have one alpha value with the 'tint()' function, which is not what I want.

There has to be a way to achieve this. Any ideas?

John_Doe YaBB Newbies Offline Posts: 18	Re: Texture fading to transparancy Reply #1 - Apr 24^th, 2008, 2:53pm Nevermind, I figured it out..

Cycleswithin YaBB Newbies Offline Posts: 36 UK	Re: Texture fading to transparancy Reply #2 - Apr 24^th, 2008, 4:56pm How did you do it?

John_Doe YaBB Newbies Offline Posts: 18	Re: Texture fading to transparancy Reply #3 - Apr 25^th, 2008, 5:45pm Actually it works with the method I posted before. Just assign that PImage as a texture to a polygon and it works. I overlooked that somewhere in my code the texture was reset to a non transparent one again..thats what u get when u try coding at 3am. =)

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