ebiten: introduce a new data structure for uniform variables instead of a map

[hajimehoshi]

• A map might not be efficient. We might keep a map, but can wrap this as an internal data structure.
• interface{} is not efficient. What about [][4]byte to represent a float, an int, and a bool?

[divVerent]

If going with [][4]byte, please provide your own helpers to convert types to that.

Or rather, make it []ebiten.ShaderUniform, where ShaderUniform is a struct containing [4]byte and has constructor functions that generate one for a float, int or bool.

That way, these binary internals are hidden, but the same efficiency is provided.

[hajimehoshi]

Or rather, make it []ebiten.ShaderUniform, where ShaderUniform is a struct containing [4]byte and has constructor functions that generate one for a float, int or bool.

This is what I intended :-)

[tinne26]

Minor point, I mentioned this on discord, but to keep it here: using uint32 directly and math.Float32bits and math.Float32frombits seems more appropriate that using [4]byte. As far as I can tell, Golang APIs tend to prefer uint* types to represent binary words if the data can fit in them.

[hajimehoshi]

This should be like

type Uniforms struct { /* ... */ }

func (u *Uniforms) AddInt(name string, value int)
func (u *Uniforms) AddVec2(name string, value [2]float32)

so that we could provide a type-safe API and hide the implementation. Let's wait for v3 anyway (probably 2027 or 2028 :-)

[tinne26]

Wouldn't Uniforms.Set*() be more accurate? And besides a Reset() or similar, a single field clear may also be relevant (e.g. Uniforms.Unset/Delete(name string)).

[hajimehoshi]

Yeah, set would be better