Adding dimensionDst in copyTextureToTexture

[Makio64]

Description

Add dstDimension parameters in copyTextureToTexture to facilitate the usage in dynamic texture drawing

renderer.copyTextureToTexture( srcTexture, dstTexture, srcRegion, dstPosition, dstDimension, level )

Solution

add dstDimension after the dstPosition or after level ( to not break existing code )

Alternatives

I guess the current workaround is to resize the texture before drawing it ?

Additional context

No response

[gkjohnson]

Is there a reason you need this functionality in copyTextureToTexture vs performing a render using a full screen quad? The copyTextureToTexture function copies data directly from the CPU to the target region in the case a texture isn't already available on the GPU. The texture's cannot be downsampled in that case so this won't be able to be easily supported in the general case.

[Makio64]

@gkjohnson : For example i have an illustration and i want to draw it in different locations and at different size into another textures.

Problem if i cant decide the dimension they will be draw at the same size everytime and then i have to load different size or as you say make different quad render.. I think it could be easily avoid with dstDimension which seems a feature include in webgpu when i check the doc.

I think this case dont apply to dataTexture like in the current example but more like a loaded initialize texture and it would be great if its supported : )

[gkjohnson]

For example i have an illustration and i want to draw it in different locations and at different size into another textures.

Right but I'm trying to understand why using a render quad to render the texture (which you can scale) is somehow not good enough for your use case? Or using sprites / points? It doesn't seem like anything you've described can't already be done. At some point the change your suggesting is just doing almost the same thing internally.

I think it could be easily avoid with dstDimension which seems a feature include in webgpu when i check the doc.

Can you explain this more?

I think this case dont apply to dataTexture like in the current example but more like a loaded initialize texture and it would be great if its supported : )

The limitations I listed don't just apply to data texture - it applies to any texture that has not been uploaded to the GPU already.

[Makio64]

Yeah I actually did it with the quad and rendertarget but i thought there was a simplier / more effiscient way to do it in webgpu

Can you explain this more?

I was checking the doc here but maybe i mistake something and its not as easy to implement as I think : https://developer.mozilla.org/en-US/docs/Web/API/GPUCommandEncoder/copyTextureToTexture#copy_texture_object_structure

The limitations I listed don't just apply to data texture - it applies to any texture that has not been uploaded to the GPU already.

Thanks for clarifying it, in my case all textures are init using renderer.initTexture but I think what i'm doing in tis particular project is a rare case.

[gkjohnson]

https://developer.mozilla.org/en-US/docs/Web/API/GPUCommandEncoder/copyTextureToTexture#copy_texture_object_structure

That function doesn't look like it lets you specify a source and destination resolution. Just a single argument for the dimensions of data being copied - other than mip level which is already supported by three.js' version. I understand the convenience but I don't think there's much if any efficiency to be gained by adding a scale capability to the copyTextureToTexture function.

[gkjohnson]

If we do wind up wanting to add this I could see it working like the following:

• Change the "dstPosition" parameter to a "dstRegion" parameter (take a Box2 or Box3), similar to "srcRegion".
• If the regions are different sizes then use blitFramebuffer with the src textures scaling filter.
• Throw an error if the src texture has not been uploaded to the GPU yet and the src / dst sizes are different.

For WebGLRenderer, at least, the changes here may be fairly small.

[Makio64]

@gkjohnson That sounds perfect and i think this feature fit well into threejs.

@Mugen87 @mrdoob @RenaudRohlinger whats your vision on this ?

[Mugen87]

What @gkjohnson has suggested sounds good to me.

[gkjohnson]

@Makio64 if you'd like to make a PR I can provide feedback and we can get it merged.