我正在渲染一个包含精灵的采摘场景。当我的光标靠近精灵时，它会注册为一种颜色并被“选中”。当您放大精灵时，这个不可见的边框会变大。
打开您的控制台以查看实时打印的 ID。将光标移近和远离大小精灵。您会看到精灵在不可见的边框上被选中。这种行为不会发生在常规几何体上，只会发生在 sprite 上。
这很奇怪，因为我正在渲染renderer.readRenderTargetPixels实际看到的内容。
我怎样才能摆脱不可见的边界以便更准确地挑选？
var renderer, scene, camera, controls;
var particles, uniforms;
var PARTICLE_SIZE = 50;
var raycaster, intersects;
var mouse, INTERSECTED;
var pickingTexture;
var numOfVertices;
init();
animate();
function init() {
container = document.getElementById('container');
scene = new THREE.Scene();
camera = new THREE.PerspectiveCamera(45, window.innerWidth / window.innerHeight, 1, 10000);
camera.position.z = 150;
//
var geometry1 = new THREE.BoxGeometry(200, 200, 200, 4, 4, 4);
var vertices = geometry1.vertices;
numOfVertices = vertices.length;
var positions = new Float32Array(vertices.length * 3);
var colors = new Float32Array(vertices.length * 3);
var sizes = new Float32Array(vertices.length);
var vertex;
var color = new THREE.Color();
for (var i = 0, l = vertices.length; i < l; i++) {
vertex = vertices[i];
vertex.toArray(positions, i * 3);
color.setHex(i + 1);
color.toArray(colors, i * 3);
sizes[i] = PARTICLE_SIZE * 0.5;
}
var geometry = new THREE.BufferGeometry();
geometry.addAttribute('position', new THREE.BufferAttribute(positions, 3));
geometry.addAttribute('customColor', new THREE.BufferAttribute(colors, 3));
geometry.addAttribute('size', new THREE.BufferAttribute(sizes, 1));
//
var material = new THREE.ShaderMaterial({
uniforms: {
// texture: {type: "t", value: THREE.ImageUtils.loadTexture("../textures/circle.png")}
texture: {type: "t", value: THREE.ImageUtils.loadTexture("../textures/disc.png")}
},
vertexShader: document.getElementById('vertexshader').textContent,
fragmentShader: document.getElementById('fragmentshader').textContent,
depthTest: false,
transparent: false
// alphaTest: 0.9
});
//
particles = new THREE.Points(geometry, material);
scene.add(particles);
//
renderer = new THREE.WebGLRenderer({
antialias: true,
alpha: true
});
renderer.setPixelRatio(window.devicePixelRatio);
renderer.setSize(window.innerWidth, window.innerHeight);
renderer.setClearColor(0xffffff);
container.appendChild(renderer.domElement);
//
raycaster = new THREE.Raycaster();
mouse = new THREE.Vector2();
//
//
window.addEventListener('resize', onWindowResize, false);
document.addEventListener('mousemove', onDocumentMouseMove, false);
// defaults are on the right (except minFilter)
var options = {
format: THREE.RGBAFormat, // THREE.RGBAFormat
type: THREE.UnsignedByteType, // THREE.UnsignedByteType
anisotropy: 1, // 1
magFilter: THREE.LinearFilter, // THREE.LinearFilter
minFilter: THREE.LinearFilter, // THREE.LinearFilter
depthBuffer: true, // true
stencilBuffer: true // true
};
pickingTexture = new THREE.WebGLRenderTarget(window.innerWidth, window.innerHeight, options);
pickingTexture.texture.generateMipmaps = false;
controls = new THREE.OrbitControls(camera, container);
controls.damping = 0.2;
controls.enableDamping = false;
}
function onDocumentMouseMove(e) {
// event.preventDefault();
mouse.x = e.clientX;
mouse.y = e.clientY;
}
function onWindowResize() {
camera.aspect = window.innerWidth / window.innerHeight;
camera.updateProjectionMatrix();
renderer.setSize(window.innerWidth, window.innerHeight);
}
function animate() {
requestAnimationFrame(animate);
controls.update();
render();
}
function render() {
pick();
renderer.render(scene, camera);
}
function pick() {
renderer.render(scene, camera, pickingTexture);
//create buffer for reading single pixel
var pixelBuffer = new Uint8Array(4);
//read the pixel under the mouse from the texture
renderer.readRenderTargetPixels(pickingTexture, mouse.x, pickingTexture.height - mouse.y, 1, 1, pixelBuffer);
//interpret the pixel as an ID
var id = ( pixelBuffer[0] << 16 ) | ( pixelBuffer[1] << 8 ) | ( pixelBuffer[2] );
if (id <= numOfVertices) console.log(id);
}body {
color: #ffffff;
background-color: #000000;
margin: 0px;
overflow: hidden;
}<script src="http://threejs.org/build/three.min.js"></script>
<script src="http://threejs.org/examples/js/controls/OrbitControls.js"></script>
<script type="x-shader/x-fragment" id="fragmentshader">
uniform sampler2D texture;
varying vec3 vColor;
void main() {
// solid squares of color
gl_FragColor = vec4( vColor, 1.0 );
}
</script>
<script type="x-shader/x-vertex" id="vertexshader">
attribute float size;
attribute vec3 customColor;
varying vec3 vColor;
void main() {
vColor = customColor;
vec4 mvPosition = modelViewMatrix * vec4( position, 1.0 );
gl_PointSize = size * ( 300.0 / length( mvPosition.xyz ) );
gl_Position = projectionMatrix * mvPosition;
}
</script>
<div id="container"></div>