scaling (pixelation)

src/text.tsx

@@ -2,20 +2,12 @@ import * as THREE from 'three';
 import { Font as FontLoader } from 'three/examples/jsm/loaders/FontLoader';
 import { TextGeometry } from 'three/examples/jsm/geometries/TextGeometry';
 import { ComponentProps } from 'preact';
-import helvetiker_regular from './fonts/helvetiker_regular.typeface.json'
-
-function runThree(canvas: HTMLCanvasElement, text: string, scale: number) {
-
-    //get canvas size
-    const Bounds = canvas.getBoundingClientRect();
+import helvetiker_regular from './fonts/helvetiker_regular.typeface.json'; //taken from threejs's website
 
+function getTextGeometry(text: string): TextGeometry {
     //get font
     const Font = new FontLoader(helvetiker_regular);
 
-    //create scene
-    const scene = new THREE.Scene();
-
-    //create text
     const geometry = new TextGeometry(text, {
         font: Font,
         size: 20,
@@ -27,55 +19,103 @@ function runThree(canvas: HTMLCanvasElement, text: string, scale: number) {
         bevelOffset: 0,
         bevelSegments: 2
     });
+    geometry.center();
+    return geometry;
+}
+
+interface runThreeArgs {
+    canvas: HTMLCanvasElement;
+    text: string;
+    zoom?: number;
+    scale?: number;
+    width?: number;
+    height?: number;
+}
+
+function runThree({ canvas, text, zoom = 1, scale = 1, width, height }: runThreeArgs) {
+
+    if (!width && !height) {
+        return;
+    }
+
+    //create scene
+    const scene = new THREE.Scene();
+
+    //create text
+    const geometry = getTextGeometry(text);
     
     //create mesh from text
-    // const material = new THREE.MeshNormalMaterial();
-    const material = new THREE.ShaderMaterial({
-        uniforms: {
-            'tDiffuse': {
-                value: null
-            },
-            'resolution': {
-                value: null
-            },
-            'pixelSize': {
-                value: 100
-            }
-        },
-        vertexShader:
-            /* glsl */
-            `
-            varying highp vec2 vUv;
-            void main() {
-                vUv = uv;
-                gl_Position = projectionMatrix * modelViewMatrix * vec4( position, 1.0 );
-            }`,
-        fragmentShader:
-            /* glsl */
-            `
-            uniform sampler2D tDiffuse;
-            uniform float pixelSize;
-            uniform vec2 resolution;
-            varying highp vec2 vUv;
-            void main(){
-                vec2 dxy = pixelSize / resolution;
-                vec2 coord = dxy * floor( vUv / dxy );
-                gl_FragColor = vec4(0.0, 0.0, 0.0, 1.0);
-            }`
-    });
+    const material = new THREE.MeshNormalMaterial();
+    // const material = new THREE.ShaderMaterial({
+    //     uniforms: {
+    //         'tDiffuse': {
+    //             value: null
+    //         },
+    //         'resolution': {
+    //             value: null
+    //         },
+    //         'pixelSize': {
+    //             value: 100
+    //         }
+    //     },
+    //     vertexShader:
+    //         /* glsl */
+    //         `
+    //         varying highp vec2 vUv;
+    //         void main() {
+    //             vUv = uv;
+    //             gl_Position = projectionMatrix * modelViewMatrix * vec4( position, 1.0 );
+    //         }`,
+    //     fragmentShader:
+    //         /* glsl */
+    //         `
+    //         uniform sampler2D tDiffuse;
+    //         uniform float pixelSize;
+    //         uniform vec2 resolution;
+    //         varying highp vec2 vUv;
+    //         void main(){
+    //             vec2 dxy = pixelSize / resolution;
+    //             vec2 coord = dxy * floor( vUv / dxy );
+    //             gl_FragColor = vec4(0.0, 0.0, 0.0, 1.0);
+    //         }`
+    // });
     const mesh = new THREE.Mesh(geometry, material);
     scene.add(mesh);
 
-    //center mesh
-    mesh.geometry.center();
+    //set canvas size
+    {
+        //get size of text
+        geometry.computeBoundingBox();
+        let textW = Math.abs(geometry.boundingBox!.min.x) + Math.abs(geometry.boundingBox!.max.x),
+            textH = Math.abs(geometry.boundingBox!.min.y) + Math.abs(geometry.boundingBox!.max.y),
+            aspect = textW / textH;
+
+        //calculate width and height
+        if (width && !height) {
+            height = width / aspect;
+        } else if (!width && height) {
+            width = height * aspect;
+        }
+
+        console.log(width! * scale, height! * scale)
+
+        canvas.width = width! * scale;
+        canvas.height = height! * scale;
+
+        canvas.style.width = `${width!}px`;
+        canvas.style.height = `${height!}px`;
+        
+    }
 
     //create camera
+    const Bounds = canvas.getBoundingClientRect();
     const camera = new THREE.PerspectiveCamera(70, Bounds.width / Bounds.height, 0.01, 1000);
-    camera.position.set(0, 0, 50 / scale);
+    camera.position.set(0, 0, 100 / zoom);
 
     //set render settings
     const renderer = new THREE.WebGLRenderer({
         antialias: false,
+        precision: 'lowp',
         canvas: canvas,
         alpha: true
     });
@@ -96,20 +136,33 @@ function runThree(canvas: HTMLCanvasElement, text: string, scale: number) {
 
 interface Text3DArgs extends ComponentProps<'canvas'> {
     children: string;
-    scale: number;
+    /**
+     * zoom < 100
+     */
+    zoom?: number;
+    scale?: number;
+
+    width?: number;
+    height?: number;
 }
 
-export default function Text3D({ children: text, scale, ...props }: Text3DArgs) {
+export default function Text3D({ children: text, zoom, scale, width, height, ...props }: Text3DArgs) {
+
+    if (!width && !height) {
+        return (null);
+    }
 
     function runRef(canvas: HTMLCanvasElement | null) {
 
         if (!canvas)
             return;
 
-        runThree(canvas, text, scale);
+        runThree({
+            canvas, text, zoom, scale, width, height
+        });
     }
 
     return (
-        <canvas {...props} ref={runRef} />
+        <canvas width={width} height={height} {...props} ref={runRef} />
     )
 }