improve handling of 'out' parameters

[electronstudio]

Not sure if Raylib uses any of these, but RayGUI certainly does. Currently to use with pyray code looks like this:

import pyray as pr

char_array = pr.ffi.new("char[20]")
pointer = pr.ffi.addressof(char_array)

pr.init_window(800, 600, "raygui")
while not pr.window_should_close():
    pr.begin_drawing()
    pr.clear_background(pr.RAYWHITE)

    pr.gui_text_input_box(pr.Rectangle(0, 0, 800, 600), "title", "message", "buttons", pointer)
    string = pr.ffi.string(char_array).decode('utf-8')
    pr.draw_text(f"Text entered: {string}", 10, 40, 10, pr.DARKGRAY)

    pr.end_drawing()
pr.close_window()

I guess the cleanest solution might be to remove those parameters entirely and replace them with tuple return values, but not sure if that can be done in automated way and I hate to special-case anything.

[electronstudio]

#121

[electronstudio]

We now throw helpful exceptions if the arguments supplied aren't pointers, except in the case of strings, because we can't determine const strings at runtime. We would have to do code generation at compile time (which may also give some speed benefits.)

[electronstudio]

@martin-lorentzon requested this for QuaternionToAxisAngle() on Discord...

Richard Smith
—
3/16/25, 7:49 PM
It would be trivial to add a helper function that does it for this particular function, but for the general case I'd consider:

• I would prefer everything in the binding to be generated programmatically. Maybe nowadays Raylib API is more stable, but in the past it would change often and so every single manually written binding eventually became unmaintained and fell behind. So I'd like to at least semi-automate it or only do it for stuff unlikely to break.

• The helper function will be slower than the original function. So do we make it an additional function that people can choose to use or not, at the cost of making the API more confusing? Or do we assume that pyray users dont really care about speed and just make it the default. Someone who cares can fallback to the raylib function after all.

Richard Smith
—
3/17/25, 2:02 PM
The only functions I can see that take 'out' parameters are QuaternionToAxisAngle() and MatrixDecompose(). Are there any others? LoadFileData() but no-one should be using that anyway.
Richard Smith
—
3/17/25, 2:11 PM
CompressData(), DecompressData(), EncodeDataBase64() but im not even sure they work in python.
LoadImageAnim(), LoadImageAnimFromMemory() but they return Image and just use an out param for the number of frames. I think could be confusing if they suddently started returning tuple (Image, int) rather than Image?
Richard Smith
—
3/17/25, 2:25 PM
ExportImageToMemory(), LoadImagePalette(), LoadFontEx(), LoadFontFromMemory(), LoadFontData(), LoadCodepoints(), GetCodepoint(), GetCodepointNext(), GetCodepointPrevious(), CodepointToUTF8(), TextSplit(), TextAppend() uses one one for in and out, LoadMaterials(), LoadModelAnimations()