xgpu/dist/xGPU/shader/VertexShader.js

XGPU is an extendable library for WebGPU that provides a higher-level, easy-to-use interface for building rendering engines or processing numeric data. It handles automatic data binding, buffer alignment, variable declarations in shaders, and more. XGPU i

// Copyright (c) 2023 Thomas Le Coz. All rights reserved.
// This code is governed by an MIT license that can be found in the LICENSE file.
import { BuiltIns } from "../BuiltIns";
import { XGPU } from "../XGPU";
import { ShaderStage } from "./shaderParts/ShaderStage";
import { ShaderStruct } from "./shaderParts/ShaderStruct";
export class VertexShader extends ShaderStage {
    //public keepRendererAspectRatio: boolean = true;
    constructor() {
        super("vertex");
    }
    build(pipeline, input) {
        //this.main.text = this.extractDebugInfo(this.main.text);
        let result = "";
        //if (this.keepRendererAspectRatio) result += "const xgpuRendererAspectRatio = " + (pipeline.renderer.width / pipeline.renderer.height).toFixed(4) + ";\n\n";
        const obj = pipeline.bindGroups.getVertexShaderDeclaration();
        result += obj.result;
        //-----
        //if the renderPipeline is "fed" by a computePipeline, the shaderStruct "input"
        //contains the output vertexBuffer from the computePipeline
        result += input.getComputeVariableDeclaration();
        //-----
        let bool = false;
        for (let i = 0; i < this.outputs.length; i++) {
            if (this.outputs[i].builtin === BuiltIns.vertexOutputs.position.builtin) {
                bool = true;
            }
        }
        if (!bool) {
            this.outputs.unshift({ name: "position", ...BuiltIns.vertexOutputs.position });
        }
        let output = new ShaderStruct("Output", [...this.outputs]);
        result += output.struct + "\n";
        //let mainFunc = this.unwrapVariableInMainFunction(obj.variables)//handleVariables();
        let constants = this.unwrapVariableInWGSL(obj.variables, this.constants.value);
        result += constants + "\n\n";
        let mainFunc = this.unwrapVariableInWGSL(obj.variables, this.main.value);
        //------
        //console.log("VertexShader.variables = ", obj.variables)
        result += "@vertex\n";
        result += "fn main(" + input.getFunctionParams() + ") -> " + output.name + "{\n";
        result += "   var output:Output;\n";
        result += mainFunc;
        result += "   return output;\n";
        result += "}\n";
        result = this.formatWGSLCode(result);
        if (XGPU.showVertexShader) {
            console.log("------------- VERTEX SHADER --------------");
            console.log(result);
            console.log("------------------------------------------");
        }
        this._shaderInfos = { code: result, output: output };
        return this._shaderInfos;
    }
}