Color::get_{r,g,b,a}8() use truncate instead of round

[dalexeev]

Godot version:
3.2.4-rc4, 4.0-dev

OS/device including version:
Kubuntu 20.10

Issue description:
These methods use truncate instead of round, which causes inconsistencies with to_html in some cases (see example below). Here are the code sections responsible for this:

godot/core/math/color.h

Lines 199 to 206 in 6eef187

	_FORCE_INLINE_ void set_r8(int32_t r8) { r = (CLAMP(r8, 0, 255) / 255.0); }
	_FORCE_INLINE_ int32_t get_r8() const { return int32_t(CLAMP(r * 255.0, 0.0, 255.0)); }
	_FORCE_INLINE_ void set_g8(int32_t g8) { g = (CLAMP(g8, 0, 255) / 255.0); }
	_FORCE_INLINE_ int32_t get_g8() const { return int32_t(CLAMP(g * 255.0, 0.0, 255.0)); }
	_FORCE_INLINE_ void set_b8(int32_t b8) { b = (CLAMP(b8, 0, 255) / 255.0); }
	_FORCE_INLINE_ int32_t get_b8() const { return int32_t(CLAMP(b * 255.0, 0.0, 255.0)); }
	_FORCE_INLINE_ void set_a8(int32_t a8) { a = (CLAMP(a8, 0, 255) / 255.0); }
	_FORCE_INLINE_ int32_t get_a8() const { return int32_t(CLAMP(a * 255.0, 0.0, 255.0)); }

godot/core/math/color.cpp

Lines 421 to 441 in 6eef187

	String _to_hex(float p_val) {
	int v = Math::round(p_val * 255);
	v = CLAMP(v, 0, 255);
	String ret;
	for (int i = 0; i < 2; i++) {
	char32_t c[2] = { 0, 0 };
	int lv = v & 0xF;
	if (lv < 10) {
	c[0] = '0' + lv;
	} else {
	c[0] = 'a' + lv - 10;
	}
	v >>= 4;
	String cs = (const char32_t *)c;
	ret = cs + ret;
	}
	return ret;
	}

Steps to reproduce:

tool
extends EditorScript

func _run():
    var c = Color.from_hsv(1/12.0, 0.25, 0.8)
    print(c.to_html(false))                    # ccb399
    print('%02x%02x%02x' % [c.r8, c.g8, c.b8]) # ccb299

Minimal reproduction project:
—

[dalexeev]

Should be:

 _FORCE_INLINE_ void set_r8(int32_t r8) { r = (CLAMP(r8, 0, 255) / 255.0); } 
 _FORCE_INLINE_ int32_t get_r8() const { return int32_t(CLAMP(Math::round(r * 255.0), 0.0, 255.0)); } 
 _FORCE_INLINE_ void set_g8(int32_t g8) { g = (CLAMP(g8, 0, 255) / 255.0); } 
 _FORCE_INLINE_ int32_t get_g8() const { return int32_t(CLAMP(Math::round(g * 255.0), 0.0, 255.0)); } 
 _FORCE_INLINE_ void set_b8(int32_t b8) { b = (CLAMP(b8, 0, 255) / 255.0); } 
 _FORCE_INLINE_ int32_t get_b8() const { return int32_t(CLAMP(Math::round(b * 255.0), 0.0, 255.0)); } 
 _FORCE_INLINE_ void set_a8(int32_t a8) { a = (CLAMP(a8, 0, 255) / 255.0); } 
 _FORCE_INLINE_ int32_t get_a8() const { return int32_t(CLAMP(Math::round(a * 255.0), 0.0, 255.0)); }