No way to set a float prop to 0.0 in tiled extension

[fmoo]

Describe the bug
Tiled extensions are unable to set map, layer properties to a float value of 0.0.

To Reproduce
Steps to reproduce the behavior:

1. use the following JS in a tiled extension:

tiled.assetOpened.connect((asset) => {
  if (asset.isTileMap) {
    asset.setProperty("autoscrollX", 1.0);
    asset.setProperty("autoscrollX", 0.0);
  }
});

2. open a map.

Expected behavior
The map contains an "autoscrollX" property set to 0.0 (a float). Level designer can easily set the property to 0.1 or 0.3 without any additional steps.

Actual behavior
The map contains an "autoscrollX" property set to 0 (an integer). Level designer must right click and "convert to float" before they can use this property with decimal values.

Media
N/A

Specifications:

• OS: Windows 11
• Tiled Version: 1.9.0

[eishiya]

This isn't limited to 0.0, it happens to any whole number, including 1.0, 34987.0, etc.

This is a known issue mentioned in the API docs, it is a limitation of JavaScript, which does not distinguish ints and floats. Tiled guesses the property type based on the type of the value you give it, but integers and whole-number floats are ambiguous.

Possible solutions I mentioned when we discussed this issue on Discord:

1. convertProperty(name, type) method that converts the current value to the desired type as well as it can. This is probably overkill, since this is only a problem with (a subset of) floats, and most conversions make no sense.
2. Optional third parameter to setProperty(), something like a forceFloat bool which is used when the value is a number, and ignored otherwise.
3. setFloatProperty(name, floatValue) method that works like setProperty, but the type is always float.

Option 2 is probably the cleanest one, from a script developer's perspective.

[bjorn]

I think I'll try adding setFloatProperty, since then we can naturally also have setColorProperty, since we have a similar problem with colors not being distinguishable from strings.

[bjorn]

I've pushed this change to a new 1.9 branch, since there was a localized string added on master so that would eventually become Tiled 1.10 now.