How to get еру current target rendertexture size?

[kripto289]

Hello,
I’m trying to copy point lights cubemaps to custom RT.
commandBuffer.Blit works only with dimension:tex2D
commandBuffer.CopyTexture(BuiltinRenderTextureType.CurrentActive, customCubemap) works correctly in case of the both textures have the same size.
But point lights shadow map size is variable (because it relative to distance to camera), so how can I get the current size of the BuiltinRenderTextureType.CurrentActive?

[kripto289]

Found the solution.

if (currentLight.type == LightType.Point)
            {
                cmd.SetGlobalTexture("ShadowmapNameCopy", target);
                var tex = (RenderTexture)Shader.GetGlobalTexture("ShadowmapNameCopy");
                if (tex != null)
                {
                    InitializeShadowMapTex(tex.width, dimension);
                    cmd.CopyTexture(tex, shadowMapRT);
                }
}

It’s worked perfectly,

but why I can’t use “Shadowmap” and should create the name copy?

var tex = (RenderTexture)Shader.GetGlobalTexture("Shadowmap");//doesn't work

cmd.SetGlobalTexture("ShadowmapNameCopy", target);
var tex = (RenderTexture)Shader.GetGlobalTexture("ShadowmapNameCopy"); //works correctly

In render code I see that name:

Also I tried to use compute shader and it works

RWStructuredBuffer<int> _ShadowMapTexSize;

[numthreads(1, 1, 1)]
void GetShadowTextureSize(uint3 id : SV_DispatchThreadID)
{
    uint width;
    uint height;
    uint levels;
    ShadowMap.GetDimensions(0, width, height, levels);
    _ShadowMapTexSize[0] = width;
}

    int GetShadowTextureSize(CommandBuffer cmd)
    {
        if (computeShader == null) computeShader = (ComputeShader)Resources.Load("KWS_CopyShadowParams");
        if (computeBuffer == null) computeBuffer = KWS_CoreUtils.GetOrUpdateBuffer<float>(ref computeBuffer, 1);

        computeShader.SetBuffer(0, "RawTestData", computeBuffer);
        cmd.SetComputeTextureParam(computeShader, 0, "ShadowMap", BuiltinRenderTextureType.CurrentActive);

        cmd.DispatchCompute(computeShader, 0, 1, 1, 1);
        var size = new int[1];
        computeBuffer_GetShadowMapSize.GetData(size);
   
   
        if (size[0] == 0 || size[0] > 4097) return -1;
        else return size[0];
    }
///
 currentLight.AddCommandBuffer(LightEvent.AfterShadowMap, cmd);

But by some reason I get 0 and 1253252345 value in first frames and I have errors in some cases with different source and destination. =/