glcanvas/js/main.js

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/* Canvas set-up */
const canvas = document.getElementsByTagName("canvas")[0];
const gl = canvas.getContext("webgl", { antialias: false, preserveDrawingBuffer: false });
var projectionMatrix = mat4.create();
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mat4.perspective(
projectionMatrix,
(45 * Math.PI) / 180,
gl.drawingBufferWidth / gl.drawingBufferHeight,
0.1, 100.0
);
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gl.viewport(0, 0, gl.drawingBufferWidth, gl.drawingBufferHeight);
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/* Load shaders */
const fetchText = async url => (await fetch(url)).text();
const vsSrc = await fetchText("/shader/my.vert");
const fsSrc = await fetchText("/shader/my.frag");
const program = compile(gl, vsSrc, fsSrc);
gl.useProgram(program);
/* WebGL set-up */
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gl.clearColor(.1137, .1254, .1294, 1.0);
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gl.enable(gl.DEPTH_TEST);
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// /* Geometry */
// var verts = new Float32Array([
// 1.0, 1.0, 1.0,
// -1.0, 1.0, 1.0,
// -1.0, -1.0, 1.0,
// 1.0, -1.0, 1.0,
// 1.0, -1.0, -1.0,
// 1.0, 1.0, -1.0,
// -1.0, 1.0, -1.0,
// -1.0, -1.0, -1.0,
// ]);
// // Indices of the vertices for each triangle
// var indices = new Uint8Array([
// 0, 1, 2, 0, 2, 3, // front
// 0, 3, 4, 0, 4, 5, // right
// 0, 5, 6, 0, 6, 1, // up
// 1, 6, 7, 1, 7, 2, // left
// 7, 4, 3, 7, 3, 2, // down
// 4, 7, 6, 4, 6, 5 // back
// ]);
const mdlSrc = await fetchText("/model/Shinji.obj");
const [verts, normals, indices] = parseObj(mdlSrc);
console.log(verts, normals, indices)
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const modelViewMatrix = mat4.create();
mat4.translate(
modelViewMatrix,
modelViewMatrix,
[0.0, 0.0, -5.0]
);
/* Get attribs/uniforms */
var a_position = gl.getAttribLocation(program, 'a_position');
var u_projectionMtx = gl.getUniformLocation(program, 'u_projectionMtx');
var u_modelViewMtx = gl.getUniformLocation(program, 'u_modelViewMtx');
var u_clock = gl.getUniformLocation(program, 'u_clock');
/* Create buffers */
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buffer(gl, verts, program, 'a_position', 3, gl.FLOAT);
buffer(gl, normals, program, 'a_normal', 3, gl.FLOAT);
/* Indices */
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gl.bindBuffer(gl.ELEMENT_ARRAY_BUFFER, gl.createBuffer());
gl.bufferData(gl.ELEMENT_ARRAY_BUFFER, indices, gl.STATIC_DRAW);
/* Utility function */
const rotate3D = (mtx, x, y, z) => {
mat4.rotate(
mtx, mtx,
x,
[1, 0, 0]
);
mat4.rotate(
mtx, mtx,
y,
[0, 1, 0]
);
mat4.rotate(
mtx, mtx,
z,
[0, 0, 1]
);
};
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rotate3D(modelViewMatrix, 0.4, 0, 0);
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/* Render */
var lastDraw = performance.now();
const draw = () => {
requestAnimationFrame(draw);
// Rotate camera
var delta = performance.now() - lastDraw + 0.001;
lastDraw = performance.now();
var r1 = 1 / delta;
var r2 = r1 * 2;
r1 = (r1 * Math.PI) / 180;
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r2 = (r2 * Math.PI) / 180;
rotate3D(modelViewMatrix, 0, r1, 0);
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// Set uniforms
gl.uniformMatrix4fv(u_projectionMtx, false, projectionMatrix);
gl.uniformMatrix4fv(u_modelViewMtx, false, modelViewMatrix);
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gl.uniform1f(u_clock, performance.now() % 4096);
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// Draw triangles
gl.clear(gl.COLOR_BUFFER_BIT | gl.DEPTH_BUFFER_BIT);
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gl.drawElements(gl.TRIANGLES, indices.length, gl.UNSIGNED_SHORT, 0);
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}
/* Start */
requestAnimationFrame(draw);