Files
claude 23135a96d1 pixel-sprite-maker: spritec - .sprite text format -> png/jpg/svg + sprite sheets
- .sprite format: single-char palette keys (hex/rgb()/CSS names/none), grid
  rows, '.' transparent by default, max 256x256 per sprite
- render/sheet/info/preview subcommands; sheets name themselves
  <base>_<cellW>x<cellH>_<cols>x<rows>.<ext> (row-major)
- SVG output RLE-merges pixel runs; JPG composites over --bg
- go tests for parser, colors, scaling, svg, sheet layout

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01MmdG9GqfSWCzts7AkDwRDh
2026-07-14 02:22:16 +02:00

271 lines
9.9 KiB
Go

package sprite
import (
"fmt"
"image/color"
"strconv"
"strings"
)
// Transparent is the color used for pixels that should not be drawn.
var Transparent = color.NRGBA{0, 0, 0, 0}
// ParseColor accepts:
//
// none | transparent | - -> fully transparent
// #RGB #RGBA #RRGGBB #RRGGBBAA -> hex
// rgb(r,g,b) rgba(r,g,b,a) -> 0-255 channels, alpha 0-255 or 0.0-1.0
// CSS named colors -> "red", "rebeccapurple", ...
func ParseColor(s string) (color.NRGBA, error) {
t := strings.ToLower(strings.TrimSpace(s))
if t == "" {
return Transparent, fmt.Errorf("empty color value")
}
switch t {
case "none", "transparent", "-":
return Transparent, nil
}
if strings.HasPrefix(t, "#") {
return parseHex(t)
}
if strings.HasPrefix(t, "rgb(") || strings.HasPrefix(t, "rgba(") {
return parseRGBFunc(t)
}
if c, ok := cssColors[t]; ok {
return c, nil
}
return Transparent, fmt.Errorf("unknown color %q (use #RRGGBB, rgb(r,g,b), a CSS color name, or 'none')", s)
}
func parseHex(t string) (color.NRGBA, error) {
h := t[1:]
var r, g, b, a uint64
var err error
dup := func(s string) (uint64, error) {
v, err := strconv.ParseUint(s, 16, 8)
return v*16 + v, err
}
a = 255
switch len(h) {
case 3, 4:
if r, err = dup(h[0:1]); err == nil {
if g, err = dup(h[1:2]); err == nil {
b, err = dup(h[2:3])
}
}
if err == nil && len(h) == 4 {
a, err = dup(h[3:4])
}
case 6, 8:
if r, err = strconv.ParseUint(h[0:2], 16, 8); err == nil {
if g, err = strconv.ParseUint(h[2:4], 16, 8); err == nil {
b, err = strconv.ParseUint(h[4:6], 16, 8)
}
}
if err == nil && len(h) == 8 {
a, err = strconv.ParseUint(h[6:8], 16, 8)
}
default:
return Transparent, fmt.Errorf("hex color %q must be #RGB, #RGBA, #RRGGBB or #RRGGBBAA", t)
}
if err != nil {
return Transparent, fmt.Errorf("invalid hex color %q", t)
}
return color.NRGBA{uint8(r), uint8(g), uint8(b), uint8(a)}, nil
}
func parseRGBFunc(t string) (color.NRGBA, error) {
open := strings.Index(t, "(")
close := strings.Index(t, ")")
if close < open {
return Transparent, fmt.Errorf("invalid color %q: missing ')'", t)
}
parts := strings.Split(t[open+1:close], ",")
if len(parts) != 3 && len(parts) != 4 {
return Transparent, fmt.Errorf("invalid color %q: want rgb(r,g,b) or rgba(r,g,b,a)", t)
}
var ch [4]uint8
ch[3] = 255
for i, p := range parts {
p = strings.TrimSpace(p)
if i == 3 && strings.Contains(p, ".") {
// CSS-style fractional alpha 0.0 - 1.0
f, err := strconv.ParseFloat(p, 64)
if err != nil || f < 0 || f > 1 {
return Transparent, fmt.Errorf("invalid alpha %q in %q (want 0.0-1.0 or 0-255)", p, t)
}
ch[3] = uint8(f*255 + 0.5)
continue
}
v, err := strconv.ParseUint(p, 10, 8)
if err != nil {
return Transparent, fmt.Errorf("invalid channel %q in %q (want 0-255)", p, t)
}
ch[i] = uint8(v)
}
return color.NRGBA{ch[0], ch[1], ch[2], ch[3]}, nil
}
// FormatColor renders a color the way it should appear in a .sprite file.
func FormatColor(c color.NRGBA) string {
if c.A == 0 {
return "none"
}
if c.A == 255 {
return fmt.Sprintf("#%02X%02X%02X", c.R, c.G, c.B)
}
return fmt.Sprintf("#%02X%02X%02X%02X", c.R, c.G, c.B, c.A)
}
// cssColors is the full CSS Color Module Level 4 named-color list.
var cssColors = map[string]color.NRGBA{
"aliceblue": {240, 248, 255, 255},
"antiquewhite": {250, 235, 215, 255},
"aqua": {0, 255, 255, 255},
"aquamarine": {127, 255, 212, 255},
"azure": {240, 255, 255, 255},
"beige": {245, 245, 220, 255},
"bisque": {255, 228, 196, 255},
"black": {0, 0, 0, 255},
"blanchedalmond": {255, 235, 205, 255},
"blue": {0, 0, 255, 255},
"blueviolet": {138, 43, 226, 255},
"brown": {165, 42, 42, 255},
"burlywood": {222, 184, 135, 255},
"cadetblue": {95, 158, 160, 255},
"chartreuse": {127, 255, 0, 255},
"chocolate": {210, 105, 30, 255},
"coral": {255, 127, 80, 255},
"cornflowerblue": {100, 149, 237, 255},
"cornsilk": {255, 248, 220, 255},
"crimson": {220, 20, 60, 255},
"cyan": {0, 255, 255, 255},
"darkblue": {0, 0, 139, 255},
"darkcyan": {0, 139, 139, 255},
"darkgoldenrod": {184, 134, 11, 255},
"darkgray": {169, 169, 169, 255},
"darkgreen": {0, 100, 0, 255},
"darkgrey": {169, 169, 169, 255},
"darkkhaki": {189, 183, 107, 255},
"darkmagenta": {139, 0, 139, 255},
"darkolivegreen": {85, 107, 47, 255},
"darkorange": {255, 140, 0, 255},
"darkorchid": {153, 50, 204, 255},
"darkred": {139, 0, 0, 255},
"darksalmon": {233, 150, 122, 255},
"darkseagreen": {143, 188, 143, 255},
"darkslateblue": {72, 61, 139, 255},
"darkslategray": {47, 79, 79, 255},
"darkslategrey": {47, 79, 79, 255},
"darkturquoise": {0, 206, 209, 255},
"darkviolet": {148, 0, 211, 255},
"deeppink": {255, 20, 147, 255},
"deepskyblue": {0, 191, 255, 255},
"dimgray": {105, 105, 105, 255},
"dimgrey": {105, 105, 105, 255},
"dodgerblue": {30, 144, 255, 255},
"firebrick": {178, 34, 34, 255},
"floralwhite": {255, 250, 240, 255},
"forestgreen": {34, 139, 34, 255},
"fuchsia": {255, 0, 255, 255},
"gainsboro": {220, 220, 220, 255},
"ghostwhite": {248, 248, 255, 255},
"gold": {255, 215, 0, 255},
"goldenrod": {218, 165, 32, 255},
"gray": {128, 128, 128, 255},
"green": {0, 128, 0, 255},
"greenyellow": {173, 255, 47, 255},
"grey": {128, 128, 128, 255},
"honeydew": {240, 255, 240, 255},
"hotpink": {255, 105, 180, 255},
"indianred": {205, 92, 92, 255},
"indigo": {75, 0, 130, 255},
"ivory": {255, 255, 240, 255},
"khaki": {240, 230, 140, 255},
"lavender": {230, 230, 250, 255},
"lavenderblush": {255, 240, 245, 255},
"lawngreen": {124, 252, 0, 255},
"lemonchiffon": {255, 250, 205, 255},
"lightblue": {173, 216, 230, 255},
"lightcoral": {240, 128, 128, 255},
"lightcyan": {224, 255, 255, 255},
"lightgoldenrodyellow": {250, 250, 210, 255},
"lightgray": {211, 211, 211, 255},
"lightgreen": {144, 238, 144, 255},
"lightgrey": {211, 211, 211, 255},
"lightpink": {255, 182, 193, 255},
"lightsalmon": {255, 160, 122, 255},
"lightseagreen": {32, 178, 170, 255},
"lightskyblue": {135, 206, 250, 255},
"lightslategray": {119, 136, 153, 255},
"lightslategrey": {119, 136, 153, 255},
"lightsteelblue": {176, 196, 222, 255},
"lightyellow": {255, 255, 224, 255},
"lime": {0, 255, 0, 255},
"limegreen": {50, 205, 50, 255},
"linen": {250, 240, 230, 255},
"magenta": {255, 0, 255, 255},
"maroon": {128, 0, 0, 255},
"mediumaquamarine": {102, 205, 170, 255},
"mediumblue": {0, 0, 205, 255},
"mediumorchid": {186, 85, 211, 255},
"mediumpurple": {147, 112, 219, 255},
"mediumseagreen": {60, 179, 113, 255},
"mediumslateblue": {123, 104, 238, 255},
"mediumspringgreen": {0, 250, 154, 255},
"mediumturquoise": {72, 209, 204, 255},
"mediumvioletred": {199, 21, 133, 255},
"midnightblue": {25, 25, 112, 255},
"mintcream": {245, 255, 250, 255},
"mistyrose": {255, 228, 225, 255},
"moccasin": {255, 228, 181, 255},
"navajowhite": {255, 222, 173, 255},
"navy": {0, 0, 128, 255},
"oldlace": {253, 245, 230, 255},
"olive": {128, 128, 0, 255},
"olivedrab": {107, 142, 35, 255},
"orange": {255, 165, 0, 255},
"orangered": {255, 69, 0, 255},
"orchid": {218, 112, 214, 255},
"palegoldenrod": {238, 232, 170, 255},
"palegreen": {152, 251, 152, 255},
"paleturquoise": {175, 238, 238, 255},
"palevioletred": {219, 112, 147, 255},
"papayawhip": {255, 239, 213, 255},
"peachpuff": {255, 218, 185, 255},
"peru": {205, 133, 63, 255},
"pink": {255, 192, 203, 255},
"plum": {221, 160, 221, 255},
"powderblue": {176, 224, 230, 255},
"purple": {128, 0, 128, 255},
"rebeccapurple": {102, 51, 153, 255},
"red": {255, 0, 0, 255},
"rosybrown": {188, 143, 143, 255},
"royalblue": {65, 105, 225, 255},
"saddlebrown": {139, 69, 19, 255},
"salmon": {250, 128, 114, 255},
"sandybrown": {244, 164, 96, 255},
"seagreen": {46, 139, 87, 255},
"seashell": {255, 245, 238, 255},
"sienna": {160, 82, 45, 255},
"silver": {192, 192, 192, 255},
"skyblue": {135, 206, 235, 255},
"slateblue": {106, 90, 205, 255},
"slategray": {112, 128, 144, 255},
"slategrey": {112, 128, 144, 255},
"snow": {255, 250, 250, 255},
"springgreen": {0, 255, 127, 255},
"steelblue": {70, 130, 180, 255},
"tan": {210, 180, 140, 255},
"teal": {0, 128, 128, 255},
"thistle": {216, 191, 216, 255},
"tomato": {255, 99, 71, 255},
"turquoise": {64, 224, 208, 255},
"violet": {238, 130, 238, 255},
"wheat": {245, 222, 179, 255},
"white": {255, 255, 255, 255},
"whitesmoke": {245, 245, 245, 255},
"yellow": {255, 255, 0, 255},
"yellowgreen": {154, 205, 50, 255},
}