I’m migrating a GLSL shader to TSL where I need a Switch statement to select a texture from an array. Playing around I think the Switch function is broken. This is the code: // Simple uv.x animation const {vec4, Switch, uv, int, min } = await import( ‘three/tsl’ ); const uv0 = uv(); const index …

Looks like it might be related to how the index is computed. Since min(uv0.x.mul(5).toInt(), 5) can return 5, but you only define cases 0–4, the switch might be hitting the default path or generating odd code in the transpiled shader. You could try clamping it to 4 instead: const index = min(uv0.x…

Not only the Switch doesn’t work but also the If. This is the r183 const {vec4, If, uv, int, min } = await import( ‘three/tsl’ ); const uv0 = uv(); const index = min(uv0.x.mul(5).toInt(), 5); const result = vec4(0,0,0,1); If(index.equal(0), () => result.assign(vec4(0, 1, 0, 1))) .ElseIf(index.equa…

but ternary does work. const {vec4, select, uv, int, min } = await import( ‘three/tsl’ ); const uv0 = uv(); const index = min(uv0.x.mul(5).toInt(), 5); const result = select(index.equal(0), vec4(0, 1, 0, 1), select(index.equal(1), vec4(1,0,0,1), select(index.equal(2), vec4(0,0,1,1), select(index.e…

Thanks, that gives something to look at. And… okey looking more comments and debugging the example, as you mention, they works fine, but only if they are inside a Fn. Not sure if this is a mandatory constraint but okey.

Does TSL Switch works?

Questions

PavelBoytchev March 3, 2026, 12:41pm 5

Switch works fine. Try in a standalone file, not in the TSL editor.

https://codepen.io/boytchev/pen/WbGrbvp?editors=0010

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Does TSL Switch works?

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