mirror of
https://github.com/PavelDoGreat/WebGL-Fluid-Simulation.git
synced 2025-10-03 17:31:53 +02:00
429 lines
22 KiB
JavaScript
429 lines
22 KiB
JavaScript
'use strict';
|
|
|
|
var canvas = document.getElementsByTagName('canvas')[0];
|
|
canvas.width = canvas.clientWidth;
|
|
canvas.height = canvas.clientHeight;
|
|
|
|
var config = {
|
|
TEXTURE_DOWNSAMPLE: 1,
|
|
DENSITY_DISSIPATION: 0.98,
|
|
VELOCITY_DISSIPATION: 0.99,
|
|
PRESSURE_DISSIPATION: 0.8,
|
|
PRESSURE_ITERATIONS: 25,
|
|
CURL: 30,
|
|
SPLAT_RADIUS: 0.0025
|
|
}
|
|
|
|
var pointers = [];
|
|
var splatStack = [];
|
|
|
|
var ref = getWebGLContext(canvas);
|
|
var gl = ref.gl;
|
|
var ext = ref.ext;
|
|
var support_linear_float = ref.support_linear_float;
|
|
startGUI();
|
|
|
|
function getWebGLContext (canvas) {
|
|
var params = { alpha: false, depth: false, stencil: false, antialias: false };
|
|
|
|
var gl = canvas.getContext('webgl2', params);
|
|
var isWebGL2 = !!gl;
|
|
if (!isWebGL2)
|
|
{ gl = canvas.getContext('webgl', params) || canvas.getContext('experimental-webgl', params); }
|
|
|
|
var halfFloat = gl.getExtension('OES_texture_half_float');
|
|
var support_linear_float = gl.getExtension('OES_texture_half_float_linear');
|
|
if (isWebGL2) {
|
|
gl.getExtension('EXT_color_buffer_float');
|
|
support_linear_float = gl.getExtension('OES_texture_float_linear');
|
|
}
|
|
|
|
gl.clearColor(0.0, 0.0, 0.0, 1.0);
|
|
|
|
var internalFormat = isWebGL2 ? gl.RGBA16F : gl.RGBA;
|
|
var internalFormatRG = isWebGL2 ? gl.RG16F : gl.RGBA;
|
|
var formatRG = isWebGL2 ? gl.RG : gl.RGBA;
|
|
var texType = isWebGL2 ? gl.HALF_FLOAT : halfFloat.HALF_FLOAT_OES;
|
|
|
|
return {
|
|
gl: gl,
|
|
ext: {
|
|
internalFormat: internalFormat,
|
|
internalFormatRG: internalFormatRG,
|
|
formatRG: formatRG,
|
|
texType: texType
|
|
},
|
|
support_linear_float: support_linear_float
|
|
};
|
|
}
|
|
|
|
function startGUI () {
|
|
var gui = new dat.GUI({ width: 300 });
|
|
gui.add(config, 'TEXTURE_DOWNSAMPLE', { Full: 0, Half: 1, Quarter: 2 }).name('resolution').onFinishChange(initFramebuffers);
|
|
gui.add(config, 'DENSITY_DISSIPATION', 0.9, 1.0).name('density diffusion');
|
|
gui.add(config, 'VELOCITY_DISSIPATION', 0.9, 1.0).name('velocity diffusion');
|
|
gui.add(config, 'PRESSURE_DISSIPATION', 0.0, 1.0).name('pressure diffusion');
|
|
gui.add(config, 'PRESSURE_ITERATIONS', 1, 60).name('iterations');
|
|
gui.add(config, 'CURL', 0, 50).name('vorticity').step(1);
|
|
gui.add(config, 'SPLAT_RADIUS', 0.0001, 0.01).name('splat radius');
|
|
|
|
var randomSplats = gui.add({ fun: function () {
|
|
splatStack.push(parseInt(Math.random() * 20) + 5);
|
|
}
|
|
}, 'fun').name('Random splats');
|
|
|
|
var github = gui.add({ fun : function () { window.open('https://github.com/PavelDoGreat/WebGL-Fluid-Simulation'); } }, 'fun').name('Github');
|
|
github.__li.className = 'cr function bigFont';
|
|
github.__li.style.borderLeft = '3px solid #8C8C8C';
|
|
var githubIcon = document.createElement('span');
|
|
github.domElement.parentElement.appendChild(githubIcon);
|
|
githubIcon.className = 'icon github';
|
|
|
|
var twitter = gui.add({ fun : function () { window.open('https://twitter.com/PavelDoGreat'); } }, 'fun').name('Twitter');
|
|
twitter.__li.className = 'cr function bigFont';
|
|
twitter.__li.style.borderLeft = '3px solid #8C8C8C';
|
|
var twitterIcon = document.createElement('span');
|
|
twitter.domElement.parentElement.appendChild(twitterIcon);
|
|
twitterIcon.className = 'icon twitter';
|
|
|
|
gui.close();
|
|
}
|
|
|
|
function pointerPrototype () {
|
|
this.id = -1;
|
|
this.x = 0;
|
|
this.y = 0;
|
|
this.dx = 0;
|
|
this.dy = 0;
|
|
this.down = false;
|
|
this.moved = false;
|
|
this.color = [30, 0, 300];
|
|
}
|
|
|
|
pointers.push(new pointerPrototype());
|
|
|
|
var GLProgram = function GLProgram (vertexShader, fragmentShader) {
|
|
var this$1 = this;
|
|
|
|
this.uniforms = {};
|
|
this.program = gl.createProgram();
|
|
|
|
gl.attachShader(this.program, vertexShader);
|
|
gl.attachShader(this.program, fragmentShader);
|
|
gl.linkProgram(this.program);
|
|
|
|
if (!gl.getProgramParameter(this.program, gl.LINK_STATUS))
|
|
{ throw gl.getProgramInfoLog(this.program); }
|
|
|
|
var uniformCount = gl.getProgramParameter(this.program, gl.ACTIVE_UNIFORMS);
|
|
for (var i = 0; i < uniformCount; i++) {
|
|
var uniformName = gl.getActiveUniform(this$1.program, i).name;
|
|
this$1.uniforms[uniformName] = gl.getUniformLocation(this$1.program, uniformName);
|
|
}
|
|
};
|
|
|
|
GLProgram.prototype.bind = function bind () {
|
|
gl.useProgram(this.program);
|
|
};
|
|
|
|
function compileShader (type, source) {
|
|
var shader = gl.createShader(type);
|
|
gl.shaderSource(shader, source);
|
|
gl.compileShader(shader);
|
|
|
|
if (!gl.getShaderParameter(shader, gl.COMPILE_STATUS))
|
|
{ throw gl.getShaderInfoLog(shader); }
|
|
|
|
return shader;
|
|
};
|
|
|
|
var baseVertexShader = compileShader(gl.VERTEX_SHADER, "\n precision highp float;\n precision mediump sampler2D;\n\n attribute vec2 aPosition;\n varying vec2 vUv;\n varying vec2 vL;\n varying vec2 vR;\n varying vec2 vT;\n varying vec2 vB;\n uniform vec2 texelSize;\n\n void main () {\n vUv = aPosition * 0.5 + 0.5;\n vL = vUv - vec2(texelSize.x, 0.0);\n vR = vUv + vec2(texelSize.x, 0.0);\n vT = vUv + vec2(0.0, texelSize.y);\n vB = vUv - vec2(0.0, texelSize.y);\n gl_Position = vec4(aPosition, 0.0, 1.0);\n }\n");
|
|
|
|
var clearShader = compileShader(gl.FRAGMENT_SHADER, "\n precision highp float;\n precision mediump sampler2D;\n\n varying vec2 vUv;\n uniform sampler2D uTexture;\n uniform float value;\n\n void main () {\n gl_FragColor = value * texture2D(uTexture, vUv);\n }\n");
|
|
|
|
var displayShader = compileShader(gl.FRAGMENT_SHADER, "\n precision highp float;\n precision mediump sampler2D;\n\n varying vec2 vUv;\n uniform sampler2D uTexture;\n\n void main () {\n gl_FragColor = texture2D(uTexture, vUv);\n }\n");
|
|
|
|
var splatShader = compileShader(gl.FRAGMENT_SHADER, "\n precision highp float;\n precision mediump sampler2D;\n\n varying vec2 vUv;\n uniform sampler2D uTarget;\n uniform float aspectRatio;\n uniform vec3 color;\n uniform vec2 point;\n uniform float radius;\n\n void main () {\n vec2 p = vUv - point.xy;\n p.x *= aspectRatio;\n vec3 splat = exp(-dot(p, p) / radius) * color;\n vec3 base = texture2D(uTarget, vUv).xyz;\n gl_FragColor = vec4(base + splat, 1.0);\n }\n");
|
|
|
|
var advectionManualFilteringShader = compileShader(gl.FRAGMENT_SHADER, "\n precision highp float;\n precision mediump sampler2D;\n\n varying vec2 vUv;\n uniform sampler2D uVelocity;\n uniform sampler2D uSource;\n uniform vec2 texelSize;\n uniform float dt;\n uniform float dissipation;\n\n vec4 bilerp (in sampler2D sam, in vec2 p) {\n vec4 st;\n st.xy = floor(p - 0.5) + 0.5;\n st.zw = st.xy + 1.0;\n vec4 uv = st * texelSize.xyxy;\n vec4 a = texture2D(sam, uv.xy);\n vec4 b = texture2D(sam, uv.zy);\n vec4 c = texture2D(sam, uv.xw);\n vec4 d = texture2D(sam, uv.zw);\n vec2 f = p - st.xy;\n return mix(mix(a, b, f.x), mix(c, d, f.x), f.y);\n }\n\n void main () {\n vec2 coord = gl_FragCoord.xy - dt * texture2D(uVelocity, vUv).xy;\n gl_FragColor = dissipation * bilerp(uSource, coord);\n gl_FragColor.a = 1.0;\n }\n");
|
|
|
|
var advectionShader = compileShader(gl.FRAGMENT_SHADER, "\n precision highp float;\n precision mediump sampler2D;\n\n varying vec2 vUv;\n uniform sampler2D uVelocity;\n uniform sampler2D uSource;\n uniform vec2 texelSize;\n uniform float dt;\n uniform float dissipation;\n\n void main () {\n vec2 coord = vUv - dt * texture2D(uVelocity, vUv).xy * texelSize;\n gl_FragColor = dissipation * texture2D(uSource, coord);\n }\n");
|
|
|
|
var divergenceShader = compileShader(gl.FRAGMENT_SHADER, "\n precision highp float;\n precision mediump sampler2D;\n\n varying vec2 vUv;\n varying vec2 vL;\n varying vec2 vR;\n varying vec2 vT;\n varying vec2 vB;\n uniform sampler2D uVelocity;\n\n vec2 sampleVelocity (in vec2 uv) {\n vec2 multiplier = vec2(1.0, 1.0);\n if (uv.x < 0.0) { uv.x = 0.0; multiplier.x = -1.0; }\n if (uv.x > 1.0) { uv.x = 1.0; multiplier.x = -1.0; }\n if (uv.y < 0.0) { uv.y = 0.0; multiplier.y = -1.0; }\n if (uv.y > 1.0) { uv.y = 1.0; multiplier.y = -1.0; }\n return multiplier * texture2D(uVelocity, uv).xy;\n }\n\n void main () {\n float L = sampleVelocity(vL).x;\n float R = sampleVelocity(vR).x;\n float T = sampleVelocity(vT).y;\n float B = sampleVelocity(vB).y;\n float div = 0.5 * (R - L + T - B);\n gl_FragColor = vec4(div, 0.0, 0.0, 1.0);\n }\n");
|
|
|
|
var curlShader = compileShader(gl.FRAGMENT_SHADER, "\n precision highp float;\n precision mediump sampler2D;\n\n varying vec2 vUv;\n varying vec2 vL;\n varying vec2 vR;\n varying vec2 vT;\n varying vec2 vB;\n uniform sampler2D uVelocity;\n\n void main () {\n float L = texture2D(uVelocity, vL).y;\n float R = texture2D(uVelocity, vR).y;\n float T = texture2D(uVelocity, vT).x;\n float B = texture2D(uVelocity, vB).x;\n float vorticity = R - L - T + B;\n gl_FragColor = vec4(vorticity, 0.0, 0.0, 1.0);\n }\n");
|
|
|
|
var vorticityShader = compileShader(gl.FRAGMENT_SHADER, "\n precision highp float;\n precision mediump sampler2D;\n\n varying vec2 vUv;\n varying vec2 vL;\n varying vec2 vR;\n varying vec2 vT;\n varying vec2 vB;\n uniform sampler2D uVelocity;\n uniform sampler2D uCurl;\n uniform float curl;\n uniform float dt;\n\n void main () {\n float L = texture2D(uCurl, vL).y;\n float R = texture2D(uCurl, vR).y;\n float T = texture2D(uCurl, vT).x;\n float B = texture2D(uCurl, vB).x;\n float C = texture2D(uCurl, vUv).x;\n vec2 force = vec2(abs(T) - abs(B), abs(R) - abs(L));\n force *= 1.0 / length(force + 0.00001) * curl * C;\n vec2 vel = texture2D(uVelocity, vUv).xy;\n gl_FragColor = vec4(vel + force * dt, 0.0, 1.0);\n }\n");
|
|
|
|
var pressureShader = compileShader(gl.FRAGMENT_SHADER, "\n precision highp float;\n precision mediump sampler2D;\n\n varying vec2 vUv;\n varying vec2 vL;\n varying vec2 vR;\n varying vec2 vT;\n varying vec2 vB;\n uniform sampler2D uPressure;\n uniform sampler2D uDivergence;\n\n vec2 boundary (in vec2 uv) {\n uv = min(max(uv, 0.0), 1.0);\n return uv;\n }\n\n void main () {\n float L = texture2D(uPressure, boundary(vL)).x;\n float R = texture2D(uPressure, boundary(vR)).x;\n float T = texture2D(uPressure, boundary(vT)).x;\n float B = texture2D(uPressure, boundary(vB)).x;\n float C = texture2D(uPressure, vUv).x;\n float divergence = texture2D(uDivergence, vUv).x;\n float pressure = (L + R + B + T - divergence) * 0.25;\n gl_FragColor = vec4(pressure, 0.0, 0.0, 1.0);\n }\n");
|
|
|
|
var gradientSubtractShader = compileShader(gl.FRAGMENT_SHADER, "\n precision highp float;\n precision mediump sampler2D;\n\n varying vec2 vUv;\n varying vec2 vL;\n varying vec2 vR;\n varying vec2 vT;\n varying vec2 vB;\n uniform sampler2D uPressure;\n uniform sampler2D uVelocity;\n\n vec2 boundary (in vec2 uv) {\n uv = min(max(uv, 0.0), 1.0);\n return uv;\n }\n\n void main () {\n float L = texture2D(uPressure, boundary(vL)).x;\n float R = texture2D(uPressure, boundary(vR)).x;\n float T = texture2D(uPressure, boundary(vT)).x;\n float B = texture2D(uPressure, boundary(vB)).x;\n vec2 velocity = texture2D(uVelocity, vUv).xy;\n velocity.xy -= vec2(R - L, T - B);\n gl_FragColor = vec4(velocity, 0.0, 1.0);\n }\n");
|
|
|
|
var textureWidth;
|
|
var textureHeight;
|
|
var density;
|
|
var velocity;
|
|
var divergence;
|
|
var curl;
|
|
var pressure;
|
|
initFramebuffers();
|
|
|
|
var clearProgram = new GLProgram(baseVertexShader, clearShader);
|
|
var displayProgram = new GLProgram(baseVertexShader, displayShader);
|
|
var splatProgram = new GLProgram(baseVertexShader, splatShader);
|
|
var advectionProgram = new GLProgram(baseVertexShader, support_linear_float ? advectionShader : advectionManualFilteringShader);
|
|
var divergenceProgram = new GLProgram(baseVertexShader, divergenceShader);
|
|
var curlProgram = new GLProgram(baseVertexShader, curlShader);
|
|
var vorticityProgram = new GLProgram(baseVertexShader, vorticityShader);
|
|
var pressureProgram = new GLProgram(baseVertexShader, pressureShader);
|
|
var gradienSubtractProgram = new GLProgram(baseVertexShader, gradientSubtractShader);
|
|
|
|
function initFramebuffers () {
|
|
textureWidth = gl.drawingBufferWidth >> config.TEXTURE_DOWNSAMPLE;
|
|
textureHeight = gl.drawingBufferHeight >> config.TEXTURE_DOWNSAMPLE;
|
|
|
|
var iFormat = ext.internalFormat;
|
|
var iFormatRG = ext.internalFormatRG;
|
|
var formatRG = ext.formatRG;
|
|
var texType = ext.texType;
|
|
|
|
density = createDoubleFBO(0, textureWidth, textureHeight, iFormat , gl.RGBA , texType, support_linear_float ? gl.LINEAR : gl.NEAREST);
|
|
velocity = createDoubleFBO(2, textureWidth, textureHeight, iFormatRG, formatRG, texType, support_linear_float ? gl.LINEAR : gl.NEAREST);
|
|
divergence = createFBO (4, textureWidth, textureHeight, iFormatRG, formatRG, texType, gl.NEAREST);
|
|
curl = createFBO (5, textureWidth, textureHeight, iFormatRG, formatRG, texType, gl.NEAREST);
|
|
pressure = createDoubleFBO(6, textureWidth, textureHeight, iFormatRG, formatRG, texType, gl.NEAREST);
|
|
}
|
|
|
|
function createFBO (texId, w, h, internalFormat, format, type, param) {
|
|
gl.activeTexture(gl.TEXTURE0 + texId);
|
|
var texture = gl.createTexture();
|
|
gl.bindTexture(gl.TEXTURE_2D, texture);
|
|
gl.texParameteri(gl.TEXTURE_2D, gl.TEXTURE_MIN_FILTER, param);
|
|
gl.texParameteri(gl.TEXTURE_2D, gl.TEXTURE_MAG_FILTER, param);
|
|
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.texImage2D(gl.TEXTURE_2D, 0, internalFormat, w, h, 0, format, type, null);
|
|
|
|
var fbo = gl.createFramebuffer();
|
|
gl.bindFramebuffer(gl.FRAMEBUFFER, fbo);
|
|
gl.framebufferTexture2D(gl.FRAMEBUFFER, gl.COLOR_ATTACHMENT0, gl.TEXTURE_2D, texture, 0);
|
|
gl.viewport(0, 0, w, h);
|
|
gl.clear(gl.COLOR_BUFFER_BIT);
|
|
|
|
return [texture, fbo, texId];
|
|
}
|
|
|
|
function createDoubleFBO (texId, w, h, internalFormat, format, type, param) {
|
|
var fbo1 = createFBO(texId , w, h, internalFormat, format, type, param);
|
|
var fbo2 = createFBO(texId + 1, w, h, internalFormat, format, type, param);
|
|
|
|
return {
|
|
get first () {
|
|
return fbo1;
|
|
},
|
|
get second () {
|
|
return fbo2;
|
|
},
|
|
swap: function () {
|
|
var temp = fbo1;
|
|
fbo1 = fbo2;
|
|
fbo2 = temp;
|
|
}
|
|
}
|
|
}
|
|
|
|
var blit = (function () {
|
|
gl.bindBuffer(gl.ARRAY_BUFFER, gl.createBuffer());
|
|
gl.bufferData(gl.ARRAY_BUFFER, new Float32Array([-1, -1, -1, 1, 1, 1, 1, -1]), gl.STATIC_DRAW);
|
|
gl.bindBuffer(gl.ELEMENT_ARRAY_BUFFER, gl.createBuffer());
|
|
gl.bufferData(gl.ELEMENT_ARRAY_BUFFER, new Uint16Array([0, 1, 2, 0, 2, 3]), gl.STATIC_DRAW);
|
|
gl.vertexAttribPointer(0, 2, gl.FLOAT, false, 0, 0);
|
|
gl.enableVertexAttribArray(0);
|
|
|
|
return function (destination) {
|
|
gl.bindFramebuffer(gl.FRAMEBUFFER, destination);
|
|
gl.drawElements(gl.TRIANGLES, 6, gl.UNSIGNED_SHORT, 0);
|
|
}
|
|
})();
|
|
|
|
var lastTime = Date.now();
|
|
multipleSplats(parseInt(Math.random() * 20) + 5);
|
|
update();
|
|
|
|
function update () {
|
|
resizeCanvas();
|
|
|
|
var dt = Math.min((Date.now() - lastTime) / 1000, 0.016);
|
|
lastTime = Date.now();
|
|
|
|
gl.viewport(0, 0, textureWidth, textureHeight);
|
|
|
|
if (splatStack.length > 0)
|
|
{ multipleSplats(splatStack.pop()); }
|
|
|
|
advectionProgram.bind();
|
|
gl.uniform2f(advectionProgram.uniforms.texelSize, 1.0 / textureWidth, 1.0 / textureHeight);
|
|
gl.uniform1i(advectionProgram.uniforms.uVelocity, velocity.first[2]);
|
|
gl.uniform1i(advectionProgram.uniforms.uSource, velocity.first[2]);
|
|
gl.uniform1f(advectionProgram.uniforms.dt, dt);
|
|
gl.uniform1f(advectionProgram.uniforms.dissipation, config.VELOCITY_DISSIPATION);
|
|
blit(velocity.second[1]);
|
|
velocity.swap();
|
|
|
|
gl.uniform1i(advectionProgram.uniforms.uVelocity, velocity.first[2]);
|
|
gl.uniform1i(advectionProgram.uniforms.uSource, density.first[2]);
|
|
gl.uniform1f(advectionProgram.uniforms.dissipation, config.DENSITY_DISSIPATION);
|
|
blit(density.second[1]);
|
|
density.swap();
|
|
|
|
for (var i = 0; i < pointers.length; i++) {
|
|
var pointer = pointers[i];
|
|
if (pointer.moved) {
|
|
splat(pointer.x, pointer.y, pointer.dx, pointer.dy, pointer.color);
|
|
pointer.moved = false;
|
|
}
|
|
}
|
|
|
|
curlProgram.bind();
|
|
gl.uniform2f(curlProgram.uniforms.texelSize, 1.0 / textureWidth, 1.0 / textureHeight);
|
|
gl.uniform1i(curlProgram.uniforms.uVelocity, velocity.first[2]);
|
|
blit(curl[1]);
|
|
|
|
vorticityProgram.bind();
|
|
gl.uniform2f(vorticityProgram.uniforms.texelSize, 1.0 / textureWidth, 1.0 / textureHeight);
|
|
gl.uniform1i(vorticityProgram.uniforms.uVelocity, velocity.first[2]);
|
|
gl.uniform1i(vorticityProgram.uniforms.uCurl, curl[2]);
|
|
gl.uniform1f(vorticityProgram.uniforms.curl, config.CURL);
|
|
gl.uniform1f(vorticityProgram.uniforms.dt, dt);
|
|
blit(velocity.second[1]);
|
|
velocity.swap();
|
|
|
|
divergenceProgram.bind();
|
|
gl.uniform2f(divergenceProgram.uniforms.texelSize, 1.0 / textureWidth, 1.0 / textureHeight);
|
|
gl.uniform1i(divergenceProgram.uniforms.uVelocity, velocity.first[2]);
|
|
blit(divergence[1]);
|
|
|
|
clearProgram.bind();
|
|
|
|
var pressureTexId = pressure.first[2];
|
|
gl.activeTexture(gl.TEXTURE0 + pressureTexId);
|
|
gl.bindTexture(gl.TEXTURE_2D, pressure.first[0]);
|
|
gl.uniform1i(clearProgram.uniforms.uTexture, pressureTexId);
|
|
gl.uniform1f(clearProgram.uniforms.value, config.PRESSURE_DISSIPATION);
|
|
blit(pressure.second[1]);
|
|
pressure.swap();
|
|
|
|
pressureProgram.bind();
|
|
gl.uniform2f(pressureProgram.uniforms.texelSize, 1.0 / textureWidth, 1.0 / textureHeight);
|
|
gl.uniform1i(pressureProgram.uniforms.uDivergence, divergence[2]);
|
|
pressureTexId = pressure.first[2];
|
|
gl.activeTexture(gl.TEXTURE0 + pressureTexId);
|
|
for (var i$1 = 0; i$1 < config.PRESSURE_ITERATIONS; i$1++) {
|
|
gl.bindTexture(gl.TEXTURE_2D, pressure.first[0]);
|
|
gl.uniform1i(pressureProgram.uniforms.uPressure, pressureTexId);
|
|
blit(pressure.second[1]);
|
|
pressure.swap();
|
|
}
|
|
|
|
gradienSubtractProgram.bind();
|
|
gl.uniform2f(gradienSubtractProgram.uniforms.texelSize, 1.0 / textureWidth, 1.0 / textureHeight);
|
|
gl.uniform1i(gradienSubtractProgram.uniforms.uPressure, pressure.first[2]);
|
|
gl.uniform1i(gradienSubtractProgram.uniforms.uVelocity, velocity.first[2]);
|
|
blit(velocity.second[1]);
|
|
velocity.swap();
|
|
|
|
gl.viewport(0, 0, gl.drawingBufferWidth, gl.drawingBufferHeight);
|
|
displayProgram.bind();
|
|
gl.uniform1i(displayProgram.uniforms.uTexture, density.first[2]);
|
|
blit(null);
|
|
|
|
requestAnimationFrame(update);
|
|
}
|
|
|
|
function splat (x, y, dx, dy, color) {
|
|
splatProgram.bind();
|
|
gl.uniform1i(splatProgram.uniforms.uTarget, velocity.first[2]);
|
|
gl.uniform1f(splatProgram.uniforms.aspectRatio, canvas.width / canvas.height);
|
|
gl.uniform2f(splatProgram.uniforms.point, x / canvas.width, 1.0 - y / canvas.height);
|
|
gl.uniform3f(splatProgram.uniforms.color, dx, -dy, 1.0);
|
|
gl.uniform1f(splatProgram.uniforms.radius, config.SPLAT_RADIUS);
|
|
blit(velocity.second[1]);
|
|
velocity.swap();
|
|
|
|
gl.uniform1i(splatProgram.uniforms.uTarget, density.first[2]);
|
|
gl.uniform3f(splatProgram.uniforms.color, color[0] * 0.3, color[1] * 0.3, color[2] * 0.3);
|
|
blit(density.second[1]);
|
|
density.swap();
|
|
}
|
|
|
|
function multipleSplats (amount) {
|
|
for (var i = 0; i < amount; i++) {
|
|
var color = [Math.random() * 10, Math.random() * 10, Math.random() * 10];
|
|
var x = canvas.width * Math.random();
|
|
var y = canvas.height * Math.random();
|
|
var dx = 1000 * (Math.random() - 0.5);
|
|
var dy = 1000 * (Math.random() - 0.5);
|
|
splat(x, y, dx, dy, color);
|
|
}
|
|
}
|
|
|
|
function resizeCanvas () {
|
|
if (canvas.width != canvas.clientWidth || canvas.height != canvas.clientHeight) {
|
|
canvas.width = canvas.clientWidth;
|
|
canvas.height = canvas.clientHeight;
|
|
initFramebuffers();
|
|
}
|
|
}
|
|
|
|
canvas.addEventListener('mousemove', function (e) {
|
|
pointers[0].moved = pointers[0].down;
|
|
pointers[0].dx = (e.offsetX - pointers[0].x) * 10.0;
|
|
pointers[0].dy = (e.offsetY - pointers[0].y) * 10.0;
|
|
pointers[0].x = e.offsetX;
|
|
pointers[0].y = e.offsetY;
|
|
});
|
|
|
|
canvas.addEventListener('touchmove', function (e) {
|
|
e.preventDefault();
|
|
var touches = e.targetTouches;
|
|
for (var i = 0; i < touches.length; i++) {
|
|
var pointer = pointers[i];
|
|
pointer.moved = pointer.down;
|
|
pointer.dx = (touches[i].pageX - pointer.x) * 10.0;
|
|
pointer.dy = (touches[i].pageY - pointer.y) * 10.0;
|
|
pointer.x = touches[i].pageX;
|
|
pointer.y = touches[i].pageY;
|
|
}
|
|
}, false);
|
|
|
|
canvas.addEventListener('mousedown', function () {
|
|
pointers[0].down = true;
|
|
pointers[0].color = [Math.random() + 0.2, Math.random() + 0.2, Math.random() + 0.2];
|
|
});
|
|
|
|
canvas.addEventListener('touchstart', function (e) {
|
|
e.preventDefault();
|
|
var touches = e.targetTouches;
|
|
for (var i = 0; i < touches.length; i++) {
|
|
if (i >= pointers.length)
|
|
{ pointers.push(new pointerPrototype()); }
|
|
|
|
pointers[i].id = touches[i].identifier;
|
|
pointers[i].down = true;
|
|
pointers[i].x = touches[i].pageX;
|
|
pointers[i].y = touches[i].pageY;
|
|
pointers[i].color = [Math.random() + 0.2, Math.random() + 0.2, Math.random() + 0.2];
|
|
}
|
|
});
|
|
|
|
window.addEventListener('mouseup', function () {
|
|
pointers[0].down = false;
|
|
});
|
|
|
|
window.addEventListener('touchend', function (e) {
|
|
var touches = e.changedTouches;
|
|
for (var i = 0; i < touches.length; i++)
|
|
{ for (var j = 0; j < pointers.length; j++)
|
|
{ if (touches[i].identifier == pointers[j].id)
|
|
{ pointers[j].down = false; } } }
|
|
}); |