Transparency

[JMidd91]

Hi,

after successfully implementing texturity into my project, for some reason I cant get my textures to display their alpha channel?

obviously ive seen the code

 Texturity.initGL('webgl',{alpha:true}); //optional parameters

and also digging deeper -

export function initGL(contextName = 'webgl', params = {}) {
    if (gl) return gl;
  
    params = Object.assign({
        alpha: false,
        antialias: false,
        depth: false
    }, params);

    element = document.createElement('canvas');
    gl = element.getContext(contextName, params);
    format = params.alpha ? gl.RGBA : gl.RGB; 

    shaderManager = new ShaderManager(gl);
    programs = shaderManager.createPrecompiledShaders();
    vertexBuffer = createBuffer();

    return gl;
}

when turning alpha to true with using

Texturity.initGL('webgl2', { alpha: true, antialias: false, depth: false } );

it doesnt seem to do anything for me?

been looking online and all i can really find is this and a few other sites that say similar things but having tried most of it, doesnt seem to help me at all unless I am doing it wrong?

many thanks

[Ni55aN]

What operations do not leave transparency?

I think this is due to existing shaders that write a value of 1 to the transparency buffer.

[JMidd91]

not sure what you mean, this is my code that i have used along side your script -

Texturity.initGL('webgl2', { alpha: true, antialias: false, depth: false } );
var fastCanvas = new Texturity.Canvas(textureSize, textureSize);

var texture = Texturity.loadTexture(img);
var previewImg = fastCanvas.drawTexture(texture, 0, 0, nodeTextureSize, nodeTextureSize).toSrc();
node.imgDiv.style.background = 'url('+ previewImg +')'

[JMidd91]

here is an example of what i mean (the right node I manually added the same png file as the node on the left)

[Ni55aN]

Ok, I got it. Seems like drawTexture() write to alpha channel value 1.0 independently to image. I'll correct it

[JMidd91]

just wondering, did this get updated? forgot about this issue haha

[Ni55aN]

Yes, I have a busy month :)

[JMidd91]

no worries, just wanted to show this thread wasnt inactive :) is it updated here? doesnt seem to be different for me? no rush though! isnt a show stopper bug for me, im just not competent enough to fix it myself haha

[Ni55aN]

I mean I forgot about this too. No updates

[Ni55aN]

You can try to replace 1.0 with a certain color value in the last parameter of vec4

[JMidd91]

if you mean this line i did actually try that with no luck, unless i am miss understanding?

[Ni55aN]

No, inside the shaders folder

[JMidd91]

ok so with your guidance i did a bit of digging / learning and found / changed this line

to the following -

gl_FragColor = vec4(texture2D(texture, texcoord).rgba);

if youre happy with this we can close this issue, i have created a pull request :)