[rlgl] Fix condition for WebGL depth texture support

[SlateyDev]

Condition looks to be incorrect. If texDepthWebGL is available, it should be using GL_DEPTH_COMPONENT16/24/32 but currently in WebGL always uses GL_DEPTH_COMPONENT which can fail especially in WebGL2.

[SlateyDev]

This does not work for ES2 as WEBGL_depth_texture extension may exist, but it does not support the formats GL_DEPTH_COMPONENT16/24/32. These formats are supported for renderbuffer but not for texImage2D in ES2 and you need to use GL_DEPTH_COMPONENT for a 16-bit depth buffer.

[raysan5]

@SlateyDev I'm reviewing this issue but I think I'm not understanding it... As per WebGL 1.0 specifications, glTexImage2D() only supports GL_DEPTH_COMPONENT for internal pixel format, so, the sized pixel formats are only assigned if !RLGL.ExtSupported.texDepthWebGL.

Checking the official specs for WebGL_depth_texture extension, no sized constant is added, actually it lists GL_DEPTH_COMPONENT as the required internal format. Also, it states:

Note: This extension is only available to WebGL1 contexts. In WebGL2, the functionality of this extension is available on the WebGL2 context by default. The constant in WebGL2 is gl.UNSIGNED_INT_24_8.

Checking WebGL 2 specs, the sized components are supported but the provided information is missleading in reference to WebGL 1.

So, I'm confused, probably the code should be reviewed to consider OpenGL ES 2.0 (WebGL 1.0) and OpenGL ES 3.0 (WebGL 2.0) separately. Did you test this functionality on the different versions? OpenGL ES 2.0, WebGL 1.0 and WebGL 2.0.

[SlateyDev]

The problem is when WebGL2 is in use, RLGL.ExtSupported.texDepthWebGL is true and so it does not use sized pixel formats and fails because it does not work with GL_DEPTH_COMPONENT as it did in WebGL1.

I haven't yet been able to test under all cases to come up with a better design that works with all of ES2, WebGL1 and WebGL2 as I also haven't played with render buffers in any of my testing yet.

[raysan5]

The problem is when WebGL2 is in use, RLGL.ExtSupported.texDepthWebGL is true and so it does not use sized pixel formats and fails because it does not work with GL_DEPTH_COMPONENT as it did in WebGL1.

Ok, now I see the issue.

I haven't yet been able to test under all cases to come up with a better design that works with all of ES2, WebGL1 and WebGL2 as I also haven't played with render buffers in any of my testing yet.

Ok, I will wait for those tests, feel free to redesign that approach if required.