javascript - Blank texture in webGL -

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i have simple quad, , simple shader (see below). load image needed texture, process it, uniform place in shader program, , send it, way has been explained in "learning webgl" examples. tested , used webgl inspector see textures i've been using , problem quad whole black. in fragment shader, line:

gl_fragcolor = texture2d( usampler, vuv);

actually sets fragment color (0,0,0,1). it's "blank" texture, or all-black alpha equals 1 texture, not same image i'm trying attach.

if encountered similar problem , knows how fix it, please tell me. it's done in chrome, --allow-file-access-from-files flag, html page, js/webgl code , image local, tested on server, no results.

vertex:

attribute vec3 avertexposition; attribute vec2 auv; uniform mat4 upmatrix; uniform mat4 umvmatrix; varying vec2 vuv; void main() { vuv = auv; gl_position = upmatrix * umvmatrix * vec4(avertexposition, 1.0); }

fragment:

uniform sampler2d usampler; varying vec2 vuv; void main() { gl_fragcolor = texture2d( usampler, vuv) }

texture loading , attaching:

var tex = new chaos.texture().load2d("ch.jpg"); var mat = new chaos.material().fromscript("v1", "f1"); mat.addtexture("usampler", tex);

loading function:

load2d: function(url) {     function handletextureloaded(image, texture, gl) {         gl.bindtexture(gl.texture_2d, texture);         gl.teximage2d(gl.texture_2d, 0, gl.rgba, gl.rgba, gl.unsigned_byte, image);         gl.texparameteri(gl.texture_2d, gl.texture_mag_filter, gl.linear);         gl.texparameteri(gl.texture_2d, gl.texture_min_filter, gl.linear_mipmap_nearest);         gl.texparameteri(gl.texture_2d, gl.texture_wrap_s, gl.clamp_to_edge);         gl.texparameteri(gl.texture_2d, gl.texture_wrap_t, gl.clamp_to_edge);         gl.generatemipmap(gl.texture_2d);         gl.bindtexture(gl.texture_2d, null);     }      var tex, im, gl = chaos.__r.context;      tex = gl.createtexture();     im = new image();     im.src = url;     im.onload = function() { handletextureloaded(im, tex, gl); }       return tex; },

and addtexture:

addtexture: function(name, texture) {     this.maps[name] = texture;     this.locunif(name); }

in render function there's part:

for(var key in mate.maps) {   gl.activetexture(gl.texture0 + tex_count); // problem int+string, don't @   gl.bindtexture(gl.texture_2d, mate.maps[key]);   gl.uniform1i(shaderprogram.unif[key], tex_count);        tex_count++; }

i declared property .isready on texture, , put on 'true' in end of image's onload callback function. in render function check if .isready , send gpu. if animation running, visible in second or third frame, depending on image size , time takes loaded. problem used local variable buffered arrays, discarded after first frame rendered (because buffer data once). fine now.

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if encounteres similar problem blank texture, check if right values being sent gl.uniform1i, check binded texture actual webgl texture object , check how attributes going.


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