WebGL-向fbo纹理渲染深度不起作用 [英] WebGL - render depth to fbo texture does not work

问题描述

对于后期处理着色器，我需要帧缓冲区的颜色和深度缓冲区.访问colorbuffer可以正常工作，但是在创建depthbuffer时遇到了问题.尝试将texImage2D用于深度纹理时，总是会收到INVALID_ENUM错误:

For a post processing shader, I need the color and the depth buffer of my framebuffer. Accessing the colorbuffer works fine but I have problems creating the depthbuffer. I always get an INVALID_ENUM error when trying to use texImage2D for the depth texture:

WebGL error INVALID_ENUM in texImage2D(TEXTURE_2D, 0, DEPTH_COMPONENT16, 1536, 502, 0, DEPTH_COMPONENT, UNSIGNED_BYTE, null)

使用渲染缓冲区代替纹理可以，但是我想要纹理的深度，以便可以将其传递给着色器.

using a renderbuffer instead of a texture works but I want depth in a texture so I can pass it to a shader.

具有深度纹理代码的帧缓冲区:

framebuffer with depth texture code:

Framebuffer.prototype.initBufferStuffTexture = function(width, height){
    if(this.width == width && this.height == height){
        return;
    }

    this.width = width;
    this.height = height;

    // remove existing buffers
    gl.bindFramebuffer(gl.FRAMEBUFFER, null);
    if(this.texture != null){
        gl.deleteTexture(this.texture.glid);
        this.texture = null;
    }
    if(this.renderbuffer != null){
        gl.deleteRenderbuffer(this.renderbuffer);
        this.renderbuffer = null;
    }
    if(this.framebuffer != null){
        gl.deleteFramebuffer(this.framebuffer);
        this.framebuffer = null;
    }

    // create new buffers
    this.framebuffer = gl.createFramebuffer();
    this.texture = new Texture();
    this.texture.glid = gl.createTexture();
    this.depth = new Texture();
    this.depth.glid = gl.createTexture();

    // framebuffer
    gl.bindFramebuffer(gl.FRAMEBUFFER, this.framebuffer);
    this.framebuffer.width = width;
    this.framebuffer.height = height;

    // colorbuffer
    gl.bindTexture(gl.TEXTURE_2D, this.texture.glid);
    gl.texParameteri(gl.TEXTURE_2D, gl.TEXTURE_MAG_FILTER, gl.NEAREST);
    gl.texParameteri(gl.TEXTURE_2D, gl.TEXTURE_MIN_FILTER, gl.NEAREST);
    gl.texParameteri(gl.TEXTURE_2D, gl.TEXTURE_WRAP_S, gl.CLAMP_TO_EDGE);
    gl.texParameteri(gl.TEXTURE_2D, gl.TEXTURE_WRAP_T, gl.CLAMP_TO_EDGE);
    gl.texImage2D(gl.TEXTURE_2D, 0, gl.RGBA, this.framebuffer.width, this.framebuffer.height, 0, gl.RGBA, gl.UNSIGNED_BYTE, null);

    // depthbuffer
    gl.bindTexture(gl.TEXTURE_2D, this.depth.glid);
    gl.texParameteri(gl.TEXTURE_2D, gl.TEXTURE_MAG_FILTER, gl.NEAREST);
    gl.texParameteri(gl.TEXTURE_2D, gl.TEXTURE_MIN_FILTER, gl.NEAREST);
    gl.texParameteri(gl.TEXTURE_2D, gl.TEXTURE_WRAP_S, gl.CLAMP_TO_EDGE);
    gl.texParameteri(gl.TEXTURE_2D, gl.TEXTURE_WRAP_T, gl.CLAMP_TO_EDGE);
    gl.texImage2D(gl.TEXTURE_2D, 0, gl.DEPTH_COMPONENT16, this.framebuffer.width, this.framebuffer.height, 0, gl.DEPTH_COMPONENT, gl.UNSIGNED_BYTE, null);

    // assemble buffers
    gl.framebufferTexture2D(gl.FRAMEBUFFER, gl.COLOR_ATTACHMENT0, gl.TEXTURE_2D, this.texture.glid, 0);
    gl.framebufferTexture2D(gl.FRAMEBUFFER, gl.DEPTH_ATTACHMENT, gl.TEXTURE_2D, this.depth.glid, 0);

    this.checkBuffer();

    gl.bindTexture(gl.TEXTURE_2D, null);
    gl.bindRenderbuffer(gl.RENDERBUFFER, null);
    gl.bindFramebuffer(gl.FRAMEBUFFER, null);
}

推荐答案

OpenGL ES 2.0规范(针对指定的WebGL)未将GL_DEPTH_COMPONENT(或其任何大小的版本)列出为有效的纹理内部格式，因此似乎不支持深度纹理，并且由于WebGL规范并未声明其行为有所不同的任何地方，因此它也不支持深度纹理.

The OpenGL ES 2.0 specification (against which WebGL was specified) doesn't list GL_DEPTH_COMPONENT (or any of its sized versions) as a valid texture internal format, so it seems not to support depth textures and as the WebGL specification doesn't state anywhere that it behaves differently, it also doesn't support depth textures.

但是也许链接很有帮助，在这里深度文字是通过将深度值打包到标准rgba纹理中在WebGL中进行仿真.

But maybe this link is of help, where depth txtures are emulated in WebGL by packing the depth value into a standard rgba texture.

这篇关于WebGL-向fbo纹理渲染深度不起作用的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！