Anistropic Filtering

Video Lecture

Anistropic Filtering Anistropic Filtering Anistropic Filtering

Description

Anisotropic Filtering allows us to improve the quality of the MIP maps.

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import * as THREE from '/build/three.module.js'
import { OrbitControls } from '/jsm/controls/OrbitControls'
import Stats from '/jsm/libs/stats.module'
import { GUI } from '/jsm/libs/dat.gui.module'

const scene1: THREE.Scene = new THREE.Scene()
const scene2: THREE.Scene = new THREE.Scene()

const axesHelper1 = new THREE.AxesHelper(5)
scene1.add(axesHelper1)
const axesHelper2 = new THREE.AxesHelper(5)
scene2.add(axesHelper2)

const camera: THREE.PerspectiveCamera = new THREE.PerspectiveCamera(75, window.innerWidth / window.innerHeight, 0.01, 1000)

const renderer: THREE.WebGLRenderer = new THREE.WebGLRenderer()
renderer.setSize(window.innerWidth, window.innerHeight)
document.body.appendChild(renderer.domElement)

const controls = new OrbitControls(camera, renderer.domElement)
controls.screenSpacePanning = true //so that panning up and down doesn't zoom in/out

const planeGeometry1: THREE.PlaneGeometry = new THREE.PlaneGeometry(2, 25)
const planeGeometry2: THREE.PlaneGeometry = new THREE.PlaneGeometry(2, 25)

//const texture1 = new THREE.TextureLoader().load("img/grid.png")
//const texture2 = new THREE.TextureLoader().load("img/grid.png")

let mipmap = (size: number, color: string) => {
    const imageCanvas = document.createElement("canvas") as HTMLCanvasElement
    const context = imageCanvas.getContext("2d") as CanvasRenderingContext2D
    imageCanvas.width = size
    imageCanvas.height = size
    context.fillStyle = "#888888"
    context.fillRect(0, 0, size, size)
    context.fillStyle = color
    context.fillRect(0, 0, size / 2, size / 2)
    context.fillRect(size / 2, size / 2, size / 2, size / 2)
    return context.getImageData(0, 0, size, size)
}

const texture1 = new THREE.CanvasTexture(document.createElement("canvas"));
texture1.mipmaps[0] = mipmap(128, '#ff0000');
texture1.mipmaps[1] = mipmap(64, '#00ff00');
texture1.mipmaps[2] = mipmap(32, '#0000ff');
texture1.mipmaps[3] = mipmap(16, '#880000');
texture1.mipmaps[4] = mipmap(8, '#008800');
texture1.mipmaps[5] = mipmap(4, '#000088');
texture1.mipmaps[6] = mipmap(2, '#008888');
texture1.mipmaps[7] = mipmap(1, '#880088');
texture1.repeat.set(5, 50);
texture1.wrapS = THREE.RepeatWrapping;
texture1.wrapT = THREE.RepeatWrapping;

const texture2 = new THREE.CanvasTexture(document.createElement("canvas"));
texture2.mipmaps[0] = mipmap(128, '#ff0000');
texture2.mipmaps[1] = mipmap(64, '#00ff00');
texture2.mipmaps[2] = mipmap(32, '#0000ff');
texture2.mipmaps[3] = mipmap(16, '#880000');
texture2.mipmaps[4] = mipmap(8, '#008800');
texture2.mipmaps[5] = mipmap(4, '#000088');
texture2.mipmaps[6] = mipmap(2, '#008888');
texture2.mipmaps[7] = mipmap(1, '#880088');
texture2.repeat.set(5, 50);
texture2.wrapS = THREE.RepeatWrapping;
texture2.wrapT = THREE.RepeatWrapping;

const material1: THREE.MeshBasicMaterial = new THREE.MeshBasicMaterial({ map: texture1 })
const material2: THREE.MeshBasicMaterial = new THREE.MeshBasicMaterial({ map: texture2 })

texture2.minFilter = THREE.NearestFilter
texture2.magFilter = THREE.NearestFilter

const plane1: THREE.Mesh = new THREE.Mesh(planeGeometry1, material1)
const plane2: THREE.Mesh = new THREE.Mesh(planeGeometry2, material2)

scene1.add(plane1)
scene2.add(plane2)

camera.position.z = 1

window.addEventListener('resize', onWindowResize, false)
function onWindowResize() {
    camera.aspect = window.innerWidth / window.innerHeight
    camera.updateProjectionMatrix()
    renderer.setSize(window.innerWidth, window.innerHeight)
    render()
}

var options = {
    minFilters: {
        "NearestFilter": THREE.NearestFilter,
        "NearestMipMapLinearFilter": THREE.NearestMipMapLinearFilter,
        "NearestMipMapNearestFilter": THREE.NearestMipMapNearestFilter,
        "LinearFilter ": THREE.LinearFilter,
        "LinearMipMapLinearFilter (Default)": THREE.LinearMipMapLinearFilter,
        "LinearMipmapNearestFilter": THREE.LinearMipmapNearestFilter
    },
    magFilters: {
        "NearestFilter": THREE.NearestFilter,
        "LinearFilter (Default)": THREE.LinearFilter,
    }
}

const gui = new GUI()
const textureFolder = gui.addFolder('THREE.Texture')
textureFolder.add(texture2, 'minFilter', options.minFilters).onChange(() => updateMinFilter())
textureFolder.add(texture2, 'magFilter', options.magFilters).onChange(() => updateMagFilter())
textureFolder.add(texture2, 'anisotropy', 1, renderer.capabilities.getMaxAnisotropy()).onChange(() => texture2.needsUpdate = true)
textureFolder.open()

function updateMinFilter() {
    texture2.minFilter = Number(texture2.minFilter)
    texture2.needsUpdate = true
}
function updateMagFilter() {
    texture2.magFilter = Number(texture2.magFilter)
    texture2.needsUpdate = true
}




const stats = Stats()
document.body.appendChild(stats.dom)

var animate = function () {
    requestAnimationFrame(animate)

    render()

    stats.update()
};

function render() {

    renderer.setScissorTest(true);

    renderer.setScissor(0, 0, window.innerWidth / 2 - 2, window.innerHeight);
    renderer.render(scene1, camera);

    renderer.setScissor(window.innerWidth / 2, 0, window.innerWidth / 2 - 2, window.innerHeight);
    renderer.render(scene2, camera);

    renderer.setScissorTest(false);

}
animate();

Anistropic Fitering