decla-red/frontend/src/scripts/drawing/renderer.ts
schmelczerandras ac66c91000 Remove twgl
2020-07-19 22:24:50 +02:00

104 lines
2.8 KiB
TypeScript

import { Drawer } from './drawer';
import { Vec2 } from '../math/vec2';
import { createProgram } from './graphics-library/create-program';
import { prepareScreenQuad } from './graphics-library/prepare-screen-quad';
export class WebGl2Renderer implements Drawer {
private gl: WebGL2RenderingContext;
private program: WebGLProgram;
private vao: WebGLVertexArrayObject;
public enableHighDpiRendering = false;
public renderScale = 0.33;
private cameraPosition: Vec2;
private viewBoxSize: Vec2;
constructor(
private canvas: HTMLCanvasElement,
private overlay: HTMLElement,
shaderSources: [string, string]
) {
this.gl = this.canvas.getContext('webgl2');
if (!this.gl) {
throw new Error('WebGl2 is not supported');
}
this.program = createProgram(this.gl, ...shaderSources);
this.vao = prepareScreenQuad(this.gl, this.program, 'a_position');
}
private handleResize() {
const realToCssPixels = window.devicePixelRatio * this.renderScale;
const displayWidth = Math.floor(this.canvas.clientWidth * realToCssPixels);
const displayHeight = Math.floor(
this.canvas.clientHeight * realToCssPixels
);
if (
this.canvas.width !== displayWidth ||
this.canvas.height !== displayHeight
) {
this.canvas.width = displayWidth;
this.canvas.height = displayHeight;
}
this.gl.viewport(0, 0, this.canvas.width, this.canvas.height);
}
public startFrame() {
this.handleResize();
this.gl.clearColor(0, 0, 0, 0);
this.gl.clear(this.gl.COLOR_BUFFER_BIT | this.gl.DEPTH_BUFFER_BIT);
this.gl.useProgram(this.program);
this.gl.bindVertexArray(this.vao);
}
finishFrame() {
const resolutionUniformLocation = this.gl.getUniformLocation(
this.program,
'resolution'
);
this.gl.uniform2f(
resolutionUniformLocation,
this.canvas.width,
this.canvas.height
);
const viewBoxSizeUniformLocation = this.gl.getUniformLocation(
this.program,
'viewBoxSize'
);
this.gl.uniform2f(viewBoxSizeUniformLocation, ...this.viewBoxSize.list);
const cameraPositionUniformLocation = this.gl.getUniformLocation(
this.program,
'cameraPosition'
);
this.gl.uniform2f(
cameraPositionUniformLocation,
...this.cameraPosition.list
);
this.gl.drawArrays(this.gl.TRIANGLE_STRIP, 0, 4);
}
setCameraPosition(position: Vec2) {
this.cameraPosition = position;
}
setInViewWidth(size: number): Vec2 {
const canvasAspectRatio =
this.canvas.clientHeight / this.canvas.clientWidth;
this.viewBoxSize = new Vec2(size, size * canvasAspectRatio);
return this.viewBoxSize;
}
drawInfoText(text: string) {
if (this.overlay.innerText != text) {
this.overlay.innerText = text;
}
}
}