Function AttribCheckColor

gui/builder.go:885–936

AttribCheckColor checks and converts attribute with color name or color component values

(b *Builder, am map[string]interface{}, fname string)

// AttribCheckColor checks and converts attribute with color name or color component values
func AttribCheckColor(b *Builder, am map[string]interface{}, fname string) error {

	// Checks if field is nil
	v := am[fname]
	if v == nil {
		return nil
	}

	// Converts to string
	fs, ok := v.(string)
	if !ok {
		return b.err(am, fname, "Not a string")
	}

	// Checks if string field is empty
	fs = strings.Trim(fs, " ")
	if fs == "" {
		return nil
	}

	// If string has 1 or 2 fields it must be a color name and optional alpha
	parts := strings.Fields(fs)
	if len(parts) == 1 || len(parts) == 2 {
		// First part must be a color name
		c, ok := math32.IsColorName(parts[0])
		if !ok {
			return b.err(am, fname, fmt.Sprintf("Invalid color name:%s", parts[0]))
		}
		c4 := math32.Color4{c.R, c.G, c.B, 1}
		if len(parts) == 2 {
			val, err := strconv.ParseFloat(parts[1], 32)
			if err != nil {
				return b.err(am, fname, fmt.Sprintf("Invalid float32 value:%s", parts[1]))
			}
			c4.A = float32(val)
		}
		am[fname] = &c4
		return nil
	}

	// Accept 3 or 4 floats values
	va, err := b.parseFloats(am, fname, 3, 4)
	if err != nil {
		return err
	}
	if len(va) == 3 {
		am[fname] = &math32.Color4{va[0], va[1], va[2], 1}
		return nil
	}
	am[fname] = &math32.Color4{va[0], va[1], va[2], va[3]}
	return nil
}

// AttribCheckBorderSizes checks and convert attribute with border sizes
func AttribCheckBorderSizes(b *Builder, am map[string]interface{}, fname string) error {