import { addSignals } from './Signals.js'
import { Util } from './Util.js'
/**
* @typedef {Object} Shader~Sampler
* A reference to a 2D texture used in the shader.
* @property {number} id - Unique identifier for the sampler
* @property {string} name - Sampler variable name in shader program (e.g., "kd" for diffuse texture)
* @property {string} label - Display label for UI/menus
* @property {Array<Object>} samplers - Array of raster definitions
* @property {number} samplers[].id - Raster identifier
* @property {string} samplers[].type - Raster type (e.g., 'color', 'normal')
* @property {boolean} [samplers[].bind=true] - Whether sampler should be bound in prepareGL
* @property {boolean} [samplers[].load=true] - Whether sampler should load from raster
* @property {Array<Object>} uniforms - Shader uniform variables
* @property {string} uniforms[].type - Data type ('vec4'|'vec3'|'vec2'|'float'|'int')
* @property {boolean} uniforms[].needsUpdate - Whether uniform needs GPU update
* @property {number} uniforms[].value - Uniform value or array of values
*/
/**
* Shader module provides WebGL shader program management for OpenLIME.
* Supports both WebGL 1.0 and 2.0/3.0 GLSL specifications with automatic version detection.
*
* Shader class manages WebGL shader programs.
* Features:
* - GLSL/ES 2.0 and 3.0 support
* - Automatic uniform management
* - Multiple shader modes
* - Filter pipeline
* - Automatic version selection
*/
class Shader {
/**
* Creates a new Shader instance.
* @param {Object} [options] - Configuration options
* @param {Array<Shader~Sampler>} [options.samplers=[]] - Texture sampler definitions
* @param {Object.<string,Object>} [options.uniforms={}] - Shader uniform variables
* @param {string} [options.label=null] - Display label for the shader
* @param {Array<string>} [options.modes=[]] - Available shader modes
* @param {number} [options.version=100] - GLSL version (100 for WebGL1, 300 for WebGL2)
* @param {boolean} [options.debug=false] - Enable debug output
* @fires Shader#update
*/
constructor(options) {
Object.assign(this, {
version: 100, //check for webglversion.
debug: false,
samplers: [],
uniforms: {},
label: null,
program: null, //webgl program
modes: [],
mode: null, // The current mode
needsUpdate: true,
tileSize: [0, 0]
});
addSignals(Shader, 'update');
Object.assign(this, options);
this.filters = [];
}
/**
* Clears all filters from the shader pipeline.
* @fires Shader#update
*/
clearFilters() {
this.filters = [];
this.needsUpdate = true;
this.emit('update');
}
/**
* Adds a filter to the shader pipeline.
* @param {Object} filter - Filter to add
* @fires Shader#update
*/
addFilter(f) {
f.shader = this;
this.filters.push(f);
this.needsUpdate = true;
f.needsUpdate = true;
this.emit('update');
}
/**
* Removes a filter from the pipeline by name.
* @param {string} name - Name of filter to remove
* @fires Shader#update
*/
removeFilter(name) {
this.filters = this.filters.filter((v) => {
return v.name != name;
});
this.needsUpdate = true;
this.emit('update');
}
/**
* Sets the current shader mode.
* @param {string} mode - Mode identifier (must be in options.modes)
* @throws {Error} If mode is not recognized
*/
setMode(mode) {
if (this.modes.indexOf(mode) == -1)
throw Error("Unknown mode: " + mode);
this.mode = mode;
this.needsUpdate = true;
}
/**
* Restores WebGL state after context loss.
* @param {WebGLRenderingContext} gl - WebGL context
* @private
*/
restoreWebGL(gl) {
this.createProgram(gl);
}
/**
* Sets tile dimensions for shader calculations.
* @param {number[]} size - [width, height] of tile
*/
setTileSize(sz) {
this.tileSize = sz;
this.needsUpdate = true;
}
/**
* Sets a uniform variable value.
* @param {string} name - Uniform variable name
* @param {number|boolean|Array} value - Value to set
* @throws {Error} If uniform doesn't exist
* @fires Shader#update
*/
setUniform(name, value) {
/**
* The event is fired when a uniform shader variable is changed.
* @event Camera#update
*/
let u = this.getUniform(name);
if (!u)
throw new Error(`Unknown '${name}'. It is not a registered uniform.`);
if ((typeof (value) == "number" || typeof (value) == "boolean") && u.value == value)
return;
if (Array.isArray(value) && Array.isArray(u.value) && value.length == u.value.length) {
let equal = true;
for (let i = 0; i < value.length; i++)
if (value[i] != u.value[i]) {
equal = false;
break;
}
if (equal)
return;
}
u.value = value;
u.needsUpdate = true;
this.emit('update');
}
/** @ignore */
completeFragShaderSrc(gl) {
let gl2 = !(gl instanceof WebGLRenderingContext);
let src = `${gl2 ? '#version 300 es' : ''}\n`;
src += `precision highp float;\n`;
src += `precision highp int;\n`;
src += `const vec2 tileSize = vec2(${this.tileSize[0]}.0, ${this.tileSize[1]}.0);\n`;
src += this.fragShaderSrc() + '\n';
for (let f of this.filters) {
src += ` // Filter: ${f.name}\n`;
src += f.fragModeSrc() + '\n';
src += f.fragSamplerSrc() + '\n';
src += f.fragUniformSrc() + '\n';
src += f.fragDataSrc() + '\n\n';
}
src += `
${gl2 ? 'out' : ''} vec4 color;
void main() {
color = data();
`;
for (let f of this.filters) {
src += `color=${f.functionName()}(color);\n`
}
src += `${gl2 ? '' : 'gl_FragColor = color;'}
}`;
return src;
}
/**
* Creates the WebGL shader program.
* @param {WebGLRenderingContext} gl - WebGL context
* @private
* @throws {Error} If shader compilation or linking fails
*/
createProgram(gl) {
let vert = gl.createShader(gl.VERTEX_SHADER);
gl.shaderSource(vert, this.vertShaderSrc(gl));
gl.compileShader(vert);
let compiled = gl.getShaderParameter(vert, gl.COMPILE_STATUS);
if (!compiled) {
Util.printSrcCode(this.vertShaderSrc(gl))
console.log(gl.getShaderInfoLog(vert));
throw Error("Failed vertex shader compilation: see console log and ask for support.");
} else if (this.debug) {
Util.printSrcCode(this.vertShaderSrc(gl))
}
let frag = gl.createShader(gl.FRAGMENT_SHADER);
gl.shaderSource(frag, this.completeFragShaderSrc(gl));
gl.compileShader(frag);
if (this.program)
gl.deleteProgram(this.program);
let program = gl.createProgram();
gl.getShaderParameter(frag, gl.COMPILE_STATUS);
compiled = gl.getShaderParameter(frag, gl.COMPILE_STATUS);
if (!compiled) {
Util.printSrcCode(this.completeFragShaderSrc(gl));
console.log(gl.getShaderInfoLog(frag));
throw Error("Failed fragment shader compilation: see console log and ask for support.");
} else if (this.debug) {
Util.printSrcCode(this.completeFragShaderSrc(gl));
}
gl.attachShader(program, vert);
gl.attachShader(program, frag);
gl.linkProgram(program);
if (!gl.getProgramParameter(program, gl.LINK_STATUS)) {
var info = gl.getProgramInfoLog(program);
throw new Error('Could not compile WebGL program. \n\n' + info);
}
//sampler units;
for (let sampler of this.samplers)
sampler.location = gl.getUniformLocation(program, sampler.name);
// filter samplers
for (let f of this.filters)
for (let sampler of f.samplers)
sampler.location = gl.getUniformLocation(program, sampler.name);
this.coordattrib = gl.getAttribLocation(program, "a_position");
gl.vertexAttribPointer(this.coordattrib, 3, gl.FLOAT, false, 0, 0);
gl.enableVertexAttribArray(this.coordattrib);
this.texattrib = gl.getAttribLocation(program, "a_texcoord");
gl.vertexAttribPointer(this.texattrib, 2, gl.FLOAT, false, 0, 0);
gl.enableVertexAttribArray(this.texattrib);
this.matrixlocation = gl.getUniformLocation(program, "u_matrix");
this.program = program;
this.needsUpdate = false;
for (let uniform of Object.values(this.allUniforms())) {
uniform.location = null;
uniform.needsUpdate = true;
}
for (let f of this.filters)
f.prepare(gl);
}
/**
* Gets a uniform variable by name.
* Searches both shader uniforms and filter uniforms.
* @param {string} name - Uniform variable name
* @returns {Object|undefined} Uniform object if found
*/
getUniform(name) {
let u = this.uniforms[name];
if (u) return u;
for (let f of this.filters) {
u = f.uniforms[name];
if (u) return u;
}
return u;
}
/**
* Returns all uniform variables associated with the shader and its filters.
* Combines uniforms from both the base shader and all active filters into a single object.
* @returns {Object.<string, Object>} Combined uniform variables
*/
allUniforms() {
const result = this.uniforms;
for (let f of this.filters) {
Object.assign(result, f.uniforms);
}
return result;
}
/**
* Updates all uniform values in the GPU.
* @param {WebGLRenderingContext} gl - WebGL context
* @private
*/
updateUniforms(gl) {
for (const [name, uniform] of Object.entries(this.allUniforms())) {
if (!uniform.location)
uniform.location = gl.getUniformLocation(this.program, name);
if (!uniform.location) //uniform not used in program
continue;
if (uniform.needsUpdate) {
let value = uniform.value;
switch (uniform.type) {
case 'vec4': gl.uniform4fv(uniform.location, value); break;
case 'vec3': gl.uniform3fv(uniform.location, value); break;
case 'vec2': gl.uniform2fv(uniform.location, value); break;
case 'float': gl.uniform1f(uniform.location, value); break;
case 'int': gl.uniform1i(uniform.location, value); break;
case 'bool': gl.uniform1i(uniform.location, value); break;
case 'mat3': gl.uniformMatrix3fv(uniform.location, false, value); break;
case 'mat4': gl.uniformMatrix4fv(uniform.location, false, value); break;
default: throw Error('Unknown uniform type: ' + u.type);
}
uniform.needsUpdate = false;
}
}
}
/**
* Gets vertex shader source code.
* Default implementation provides basic vertex transformation and texture coordinate passing.
* @param {WebGLRenderingContext} gl - WebGL context
* @returns {string} Vertex shader source code
*/
vertShaderSrc(gl) {
let gl2 = !(gl instanceof WebGLRenderingContext);
return `${gl2 ? '#version 300 es' : ''}
precision highp float;
precision highp int;
uniform mat4 u_matrix;
${gl2 ? 'in' : 'attribute'} vec4 a_position;
${gl2 ? 'in' : 'attribute'} vec2 a_texcoord;
${gl2 ? 'out' : 'varying'} vec2 v_texcoord;
void main() {
gl_Position = u_matrix * a_position;
v_texcoord = a_texcoord;
} `;
}
/**
* Gets fragment shader source code.
* Must be overridden in derived classes for custom shading.
* @param {WebGLRenderingContext} gl - WebGL context
* @returns {string} Fragment shader source code
* @virtual
*/
fragShaderSrc(gl) {
let gl2 = !(gl instanceof WebGLRenderingContext);
let str = `
uniform sampler2D kd;
${gl2 ? 'in' : 'varying'} vec2 v_texcoord;
vec4 data() {
return texture${gl2 ? '' : '2D'}(kd, v_texcoord);
}
`;
return str;
}
}
/**
* Fired when shader state changes (uniforms, filters, etc).
* @event Shader#update
*/
export { Shader }