我在渲染阴影贴图时启用了gl.DEPTH_TEST。 我使用rgb包装获取深度信息。 当我将场景渲染到阴影贴图中时,深度测试不起作用。 一些较近的物体被绘制在一些较近的物体上。
阴影贴图着色器:
<script id="shadow-shader-fs" type="x-shader/x-fragment">
precision mediump float;
const float basis = 128.0;
varying vec4 vPosition;
void main(void) {
float z = vPosition.z / vPosition.w;
float x = floor(z * (basis * basis * basis - 1.0));
float b = floor(mod(x,basis)) / basis;
x = floor(x / basis);
float g = floor(mod(x,basis)) / basis;
x /= basis;
float r = floor(mod(x,basis)) / basis;
x /= basis;
gl_FragColor = vec4(r,g,b,1.0);
}
</script>
<script id="shadow-shader-vs" type="x-shader/x-vertex">
attribute vec3 aVertexPosition;
uniform mat4 uMVMatrix;
uniform mat4 uPMatrix;
varying vec4 vPosition;
void main(void) {
vPosition = uPMatrix * uMVMatrix * vec4(aVertexPosition, 1.0);
gl_Position = vPosition;
}
</script>
出来了: a Chess 3D
一个棋子在国王面前呈现。
设置代码:
function SpotLight(gl,loc,dir,minCos,col,en) {
this.location = loc;
this.direction = dir;
this.minCos = minCos;
this.color = col;
this.enabled = en;
this.pMatrix = mat4.create();
this.mvMatrix = mat4.create();
this.childMatrixStack = new MatrixStack(30);
this.frameBuffer = gl.createFramebuffer();
gl.bindFramebuffer(gl.FRAMEBUFFER, this.frameBuffer);
this.frameBuffer.width = 512;
this.frameBuffer.height = 512;
this.shadowMap = gl.createTexture();
gl.bindTexture(gl.TEXTURE_2D,this.shadowMap);
gl.texParameteri(gl.TEXTURE_2D, gl.TEXTURE_MAG_FILTER, gl.NEAREST);
gl.texParameteri(gl.TEXTURE_2D, gl.TEXTURE_MIN_FILTER, gl.NEAREST);
gl.texImage2D(gl.TEXTURE_2D, 0, gl.RGBA, this.frameBuffer.width, this.frameBuffer.height, 0, gl.RGBA, gl.UNSIGNED_BYTE, null);
this.renderBuffer = gl.createRenderbuffer();
gl.bindRenderbuffer(gl.RENDERBUFFER, this.renderBuffer);
gl.renderbufferStorage(gl.RENDERBUFFER, gl.DEPTH_COMPONENT16, this.frameBuffer.width, this.frameBuffer.height);
gl.framebufferTexture2D(gl.FRAMEBUFFER, gl.COLOR_ATTACHMENT0, gl.TEXTURE_2D, this.shadowMap, 0);
gl.framebufferRenderbuffer(gl.FRAMEBUFFER, gl.DEPTH_ATTACHMENT, gl.RENDERBUFFER, this.renderbuffer);
gl.bindTexture(gl.TEXTURE_2D, null);
gl.bindRenderbuffer(gl.RENDERBUFFER, null);
gl.bindFramebuffer(gl.FRAMEBUFFER, null);
}