Reading pixels from a HalfFloat RenderTarget

Questions
1

Hi all,

rewriting my question because it was very malformed…

How is it possible to read back pixels from a HalfFloat renderTarget ?

I’ve tried with this

const readPixel = new Float32Array(4);
renderer.readRenderTargetPixels(customPass.renderTarget, customPass.renderTarget.width*0.5, customPass.renderTarget.height*0.5, 1, 1, readPixel);

but as the array is float32 and not float16, I get only zeroes values.

If my rendertarget is set to FloatType then I get correct values. But I would like to have same results using HalfFloatType is possible.

Thanks a lot for your help

Eric

2

In HalfFloatType, the readPixel data type must be Uint16Array. But there is packing issue.
It needs to write original shader for half or float32 packing.
Maybe GL_RGBA32FEXT/ARB and GL_RGBA16FEXT/ARB are required, but Threejs seems to not supported.

I always change CubeMapRenderTarget(UnsignedByteType) when export. After exported, it just back to HalfFloat map.