OES_texture_float扩展名的使用 [英] OES_texture_float extension use

问题描述

如何使用OES_texture_float扩展名? 我不明白是否有必要在texImage2D函数中指定参数.

How to use the OES_texture_float extension? I do not understand that it is necessary to specify the arguments the function texImage2D.

var fb=gl.createFramebuffer();
gl.bindFramebuffer(gl.FRAMEBUFFER, fb);

var rb=gl.createRenderbuffer();
gl.bindRenderbuffer(gl.RENDERBUFFER, rb);
gl.renderbufferStorage(gl.RENDERBUFFER, gl.DEPTH_COMPONENT16,size[0],size[1]);
gl.framebufferRenderbuffer(gl.FRAMEBUFFER, gl.DEPTH_ATTACHMENT,gl.RENDERBUFFER, rb);

var texture=gl.createTexture();
gl.bindTexture(gl.TEXTURE_2D, texture);
gl.texParameteri(gl.TEXTURE_2D, gl.TEXTURE_MAG_FILTER, gl.LINEAR);
gl.texParameteri(gl.TEXTURE_2D, gl.TEXTURE_MIN_FILTER, gl.LINEAR);
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, size[0], size[1],0, gl.RGBA, ???, ???);

gl.framebufferTexture2D(gl.FRAMEBUFFER, gl.COLOR_ATTACHMENT0,gl.TEXTURE_2D, texture, 0);

您需要写些什么而不是"???"

What you need to write instead of "???"

推荐答案

假设您启用了扩展名，则其gl.texImage2D(gl.TEXTURE_2D, 0, gl.RGBA, size[0], size[1],0, gl.RGBA, gl.FLOAT, null);

Assuming you have the extension enabled, its gl.texImage2D(gl.TEXTURE_2D, 0, gl.RGBA, size[0], size[1],0, gl.RGBA, gl.FLOAT, null);

但是，有一个大洞穴. OES_texture_float扩展名不能保证您将能够渲染到浮点纹理.这只是意味着您可以创建和读取浮点纹理.允许您呈现浮动效果的实际扩展名是 WEBGL_color_buffer_float .但是，如果浏览器支持该扩展名，则不会显示该扩展名.因此，您必须

HOWEVER, there is a BIG CAVEAT. OES_texture_float extension doesnt guarantee that you will be able to render to a floating point texture. It just means you can create and read from float point texture. The actual extension that allows you to render to float is WEBGL_color_buffer_float. BUT browsers do not bother to show this extension if they support it. So you have to do

if (gl.checkFramebufferStatus(gl.FRAMEBUFFER) !== gl.FRAMEBUFFER_COMPLETE){
    // cant render
}

检查将纹理附加到FBO之后是否可以真正渲染浮动纹理.

to check if you can actually render to float textures after you attach the textures to FBO.

来源:花了几个小时来弄清楚为什么该事物即使支持OES_texture_float扩展也无法在IE中工作.

Source: spent hours to figure out why the thing isnt working in IE even though it supports OES_texture_float extension.

另外请注意，除非您同时启用了OES_texture_float_linear扩展名(自2015年8月起在大多数移动设备上不可用)，否则您不能对浮点纹理使用gl.LINEAR过滤

Also be aware that you can not use gl.LINEAR filtering with floating point textures unless you also enable the OES_texture_float_linear extension which is not available on most mobile devices as of August 2015

这篇关于OES_texture_float扩展名的使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！