Merge pull request #48 from Reokodoku/qoi

Add QOI image format

src/hevi.zig

@@ -152,6 +152,7 @@ pub const default_palette: ColorPalette = .{
 pub const Parser = enum {
     elf,
     pe,
+    qoi,
     data,
 
     pub const Meta = struct {
@@ -162,6 +163,7 @@ pub const Parser = enum {
         return switch (self) {
             .elf => @import("parsers/elf.zig"),
             .pe => @import("parsers/pe.zig"),
+            .qoi => @import("parsers/qoi.zig"),
             .data => @import("parsers/data.zig"),
         };
     }

src/parsers/qoi.zig

@@ -0,0 +1,29 @@
+const std = @import("std");
+const hevi = @import("../hevi.zig");
+
+pub const meta = hevi.Parser.Meta{
+    .description = "QOI (Quite OK Image)",
+};
+
+const QoiHeader = packed struct {
+    magic: u32,
+    width: u32,
+    height: u32,
+    channels: u8,
+    colorspace: u8,
+};
+
+pub fn matches(data: []const u8) bool {
+    return std.mem.startsWith(u8, data, "qoif");
+}
+
+fn setRange(colors: []hevi.PaletteColor, offset: usize, len: usize, color: hevi.PaletteColor) void {
+    @memset(colors[offset .. offset + len], color);
+}
+
+pub fn getColors(colors: []hevi.PaletteColor, _: []const u8) void {
+    @memset(colors, .normal_alt);
+
+    setRange(colors, 0, @sizeOf(QoiHeader), .c1);
+    setRange(colors, @offsetOf(QoiHeader, "magic"), @sizeOf(u32), .c1_accent);
+}