Most common errors with the Shadertoy utility

[Vipitis]

This issue lists the most common issue with shadercode with shaders from the website. It serves as a task list and will be updated as PRs are merged. (the data is based on a filtered dataset I mined a while ago)

number of shaders: 13576
number of valid shaders: 11481
number of errors during validation: 1958
number of value errors: 26
number of timeouts during validation: 10
number of panics during validation: 101

The most frequent errors are as follows:

naga:: Composing 0's component type is not expected                                                             231
InvalidToken(In, [Token(Void), Token(Struct), TypeName])                                                        117
naga:: The `return` value None does not match the function return value                                         114
panic                                                                                                           101
SemanticError("uniform/buffer blocks require layout(binding=X)")                                                 74
SemanticError("Unknown function 'dot'")                                                                          71
naga:: Type flags TypeFlags(DATA | COPY | HOST_SHAREABLE) do not meet the required TypeFlags(CONSTRUCTIBLE)      61
SemanticError("Can't resolve type: IncompatibleOperands(\"Dot(Scalar(Scalar { kind: Float, width: 4 }), _)\")")  60
SemanticError("Not implemented as constant expression: Normalize built-in function")                             58
SemanticError("Not implemented as constant expression: Acos built-in function")                                  54
SemanticError("Not implemented as constant expression: Sqrt built-in function")                                  52
PreprocessorError(DefineRedefined)                                                                               48
naga:: The type is not constructible                                                                             47
InvalidToken(Identifier("sampler2D"), [Token(RightParen)])                                                       42
SemanticError("Not implemented as constant expression: Cos built-in function")                                   36
SemanticError("Not implemented as constant expression: Fract built-in function")                                 29
invalid Shader Code                                                                                              26
SemanticError("Float literal is infinite")                                                                       23
SemanticError("Not implemented as constant expression: Atan built-in function")                                  22
SemanticError("Not implemented as constant expression: Radians built-in function")                               20
naga:: Local variable has a type [17] that can't be stored in a local variable.                                  15
naga:: Local variable has a type [10] that can't be stored in a local variable.                                  13
SemanticError("Can't lookup field on this type \"y\"")                                                           12
SemanticError("Can't lookup field on this type \"xz\"")                                                          11
other: timedout                                                                                                  10
naga:: Local variable has a type [11] that can't be stored in a local variable.                                   9
SemanticError("Not implemented as constant expression: Asin built-in function")                                   9
SemanticError("Not implemented as constant expression: Log built-in function")                                    9
SemanticError("Unknown function 'cos'")                                                                           8
SemanticError("Not implemented as constant expression: Sin built-in function")                                    8
SemanticError("Unknown function 'Rot2Cs'")                                                                        7
SemanticError("Unknown function 'inPolygon'")                                                                     7

Tasks list:

• in wgpu-py shadertoy

• Add iDate builtin to Shadertoy utility wgpu-py#428 (Unknown variable: iDate) +216 (forgot to adjust the order in the docstring)
• Add texture input to Shadertoy util (iChannel0, ...) wgpu-py#443 (Unknown variable: iChannel0, textures?) +92
• Add iFrameRate builtin to Shadertoy utility wgpu-py#453 (Unknown variable: iFrameRate) +4
• Add iChannelResolution uniform #18 (Unknown variable: iChannelResolution)
• GLSL keywords used as identifiers #22, Change names in input struct #23 (InvalidToken( ... ) +167

• in wgpu/naga

• [glsl-in] switch case using const int causes downstream panic gfx-rs/wgpu#4644 (fall-through switch case block/panic glsl -> wgsl: Case values can only be integers) (maybe fixed with wgpu-native 0.18.1.2 this example now works: https://www.shadertoy.com/view/DtccWr)
• panic during translation .frag -> .spv (validation successful): entered unreachable code gfx-rs/wgpu#4549 (glsl -> spv: panic ~block.rs:2098:56)
• [glsl-in] naga panic: index out of bound in swizzle expression gfx-rs/wgpu#4773 (valid: panic ~variables.rs:336:28) (available by wpgp-py 0.14.0) +50
• [glsl-in] Matrix construction inconsistencies and errors gfx-rs/wgpu#4897 (Composing 0's component type is not expected)
• [meta] Constant evaluator built-in functions support gfx-rs/wgpu#4507 (Not implemented as constant expression: ...) tracking several
• [glsl-in] explicitly sizing unsized arrays causes validation errors gfx-rs/wgpu#5206 (Type flags TypeFlags(DATA | COPY | HOST_SHAREABLE) do not meet the required TypeFlags(CONSTRUCTIBLE) and The type is not constructible)
• [glsl-in] UnknownType when using sampler as function parameter gfx-rs/wgpu#5256 (InvalidToken(Identifier("sampler2D")))

[almarklein]

Should this issue remain open as kind of an overview or do you prefer to only have the relevant issues/PR to specific errors?

I think this can be a nice overview. You can also keep a list in the top post where you link to all the issues and PR's that come from this work. This can then function as a "meta-issue" to track the matureness of the shadertoy util!

[Vipitis]

I cleaned up the top comment to act as a task list.

[Vipitis]

@Korijn could you transfer this issue to the shadertoy repo?

[Korijn]

@Korijn could you transfer this issue to the shadertoy repo?

Done!