sdf-2d/src/graphics/graphics-library/frame-buffer/frame-buffer.ts
2020-09-23 16:27:02 +02:00

51 lines
1.6 KiB
TypeScript

import { vec2 } from 'gl-matrix';
import { UniversalRenderingContext } from '../universal-rendering-context';
export abstract class FrameBuffer {
public renderScale = 1;
public enableHighDpiRendering = false;
protected size = vec2.create();
// null means the default framebuffer
protected frameBuffer: WebGLFramebuffer | null = null;
constructor(protected readonly gl: UniversalRenderingContext) {}
public bindAndClear(inputTextures: Array<WebGLTexture>) {
this.gl.bindFramebuffer(this.gl.FRAMEBUFFER, this.frameBuffer);
inputTextures.forEach((t, i) => {
this.gl.activeTexture(this.gl.TEXTURE0 + i);
this.gl.bindTexture(this.gl.TEXTURE_2D, t);
});
this.gl.viewport(0, 0, this.size.x, this.size.y);
this.gl.clearColor(0, 0, 0, 0);
this.gl.clear(this.gl.COLOR_BUFFER_BIT | this.gl.DEPTH_BUFFER_BIT);
}
public destroy(): void {
this.gl.deleteFramebuffer(this.frameBuffer);
}
public setSize(): boolean {
const realToCssPixels =
(this.enableHighDpiRendering ? window.devicePixelRatio : 1) * this.renderScale;
const canvasWidth = (this.gl.canvas as HTMLCanvasElement).clientWidth;
const canvasHeight = (this.gl.canvas as HTMLCanvasElement).clientHeight;
const displayWidth = Math.floor(canvasWidth * realToCssPixels);
const displayHeight = Math.floor(canvasHeight * realToCssPixels);
const oldSize = vec2.clone(this.getSize());
this.size = vec2.fromValues(displayWidth, displayHeight);
return this.size.x != oldSize.x || this.size.y != oldSize.y;
}
public getSize(): vec2 {
return this.size;
}
}