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copied!<p>I have a sphere tessellation algorithm using a icosahedron. There are plenty of places on the net to find them but feel free to use and modify my implementation. Though i must say, my implementation is not the best when it come to memory, some vertices are duplicates. </p> <pre><code> function initSphere(subs){ if(typeof(subs) == 'undefined'){ subs = 1; } var t = (1+Math.sqrt(5))/2; var tau = t/Math.sqrt(1+t*t); var one = 1/Math.sqrt(1+t*t); var pos = [tau, one, 0.0, -tau, one, 0.0, -tau, -one, 0.0, tau, -one, 0.0, one, 0.0 , tau, one, 0.0 , -tau, -one, 0.0 , -tau, -one, 0.0 , tau, 0.0 , tau, one, 0.0 , -tau, one, 0.0 , -tau, -one, 0.0 , tau, -one]; var _indices = [4, 8, 7, 4, 7, 9, 5, 6, 11, 5, 10, 6, 0, 4, 3, 0, 3, 5, 2, 7, 1, 2, 1, 6, 8, 0, 11, 8, 11, 1, 9, 10, 3, 9, 2, 10, 8, 4, 0, 11, 0, 5, 4, 9, 3, 5, 3, 10, 7, 8, 1, 6, 1, 11, 7, 2, 9, 6, 10, 2]; for(var i = 0;i<subs;i++){ var newIndices = new Array(); for(var j = 0;j<_indices.length;j+=3){ var p1 = [ (pos[_indices[j+0]*3+0] + pos[_indices[j+1]*3+0])*0.5 , (pos[_indices[j+0]*3+1] + pos[_indices[j+1]*3+1])*0.5 , (pos[_indices[j+0]*3+2] + pos[_indices[j+1]*3+2])*0.5 ]; var p2 = [ (pos[_indices[j+1]*3+0] + pos[_indices[j+2]*3+0])*0.5 , (pos[_indices[j+1]*3+1] + pos[_indices[j+2]*3+1])*0.5 , (pos[_indices[j+1]*3+2] + pos[_indices[j+2]*3+2])*0.5 ]; var p3 = [ (pos[_indices[j+2]*3+0] + pos[_indices[j+0]*3+0])*0.5 , (pos[_indices[j+2]*3+1] + pos[_indices[j+0]*3+1])*0.5 , (pos[_indices[j+2]*3+2] + pos[_indices[j+0]*3+2])*0.5 ]; p1 = normalize(p1); p2 = normalize(p2); p3 = normalize(p3); var i0,i1,i2,a,b,c; i0 = pos.length/3; i1 = pos.length/3+1; i2 = pos.length/3+2; a = _indices[j+0]; b = _indices[j+1]; c = _indices[j+2]; newIndices.push(a);newIndices.push(i2);newIndices.push(i0); newIndices.push(b);newIndices.push(i0);newIndices.push(i1); newIndices.push(c);newIndices.push(i1);newIndices.push(i2); newIndices.push(i0);newIndices.push(i2);newIndices.push(i1); pos.push(p1[0]);pos.push(p1[1]);pos.push(p1[2]); pos.push(p2[0]);pos.push(p2[1]);pos.push(p2[2]); pos.push(p3[0]);pos.push(p3[1]);pos.push(p3[2]); } _indices = newIndices; } gl.bindBuffer(gl.ARRAY_BUFFER,sphereBuffer); gl.bufferData(gl.ARRAY_BUFFER,new Float32Array(pos),gl.STATIC_DRAW); gl.bindBuffer(gl.ELEMENT_ARRAY_BUFFER,sphereIndexBuffer); gl.bufferData(gl.ELEMENT_ARRAY_BUFFER,new Uint16Array(_indices),gl.STATIC_DRAW); sphereIndexBuffer.num = _indices.length; } </code></pre>

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