From bf59ac0d92248aa65b8a1552a30ffe6d7adf7e65 Mon Sep 17 00:00:00 2001
From: Rekai Musuka <rekai@musuka.dev>
Date: Fri, 13 May 2022 11:52:54 -0300
Subject: [PATCH] chore: use A or B to cycle through sprite shape types

---
 src/2d_sprites.zig | 98 +++++++++++++++++++++++++---------------------
 1 file changed, 54 insertions(+), 44 deletions(-)

diff --git a/src/2d_sprites.zig b/src/2d_sprites.zig
index 99fe8b2..5438641 100644
--- a/src/2d_sprites.zig
+++ b/src/2d_sprites.zig
@@ -9,30 +9,12 @@ const Input = @import("gba").Input;
 const SquareSpriteTuple = std.meta.Tuple(&[_]type{ Sprite8x8, Sprite16x16, Sprite32x32, Sprite64x64 });
 const HorizSpriteTuple = std.meta.Tuple(&[_]type{ Sprite16x8, Sprite32x8, Sprite32x16, Sprite64x32 });
 const VertSpriteTuple = std.meta.Tuple(&[_]type{ Sprite8x16, Sprite8x32, Sprite16x32, Sprite32x64 });
+const SpriteTupleTuple = std.meta.Tuple(&[_]type{ SquareSpriteTuple, HorizSpriteTuple, VertSpriteTuple });
+const sprites = initSpriteTupleTuple();
 
 // TODO: ZigGBA should support spaces, slashes, underscores, etc. in ROM Title
 export var gameHeader linksection(".gbaheader") = GBA.Header.setup("2DSPRITE", "PAOD", "00", 0);
 
-// To-do List:
-// TODO: 8BPP variants?
-// TODO: Tall Sprites
-
-const square_sprites = initSquareSpriteTuple();
-const horiz_sprites = initHorizSpriteTuple();
-const vert_sprites = initVertSpriteTuple();
-
-fn initSquareSpriteTuple() SquareSpriteTuple {
-    return .{ Sprite8x8{}, Sprite16x16{}, Sprite32x32{}, Sprite64x64{} };
-}
-
-fn initHorizSpriteTuple() HorizSpriteTuple {
-    return .{ Sprite16x8{}, Sprite32x8{}, Sprite32x16{}, Sprite64x32{} };
-}
-
-fn initVertSpriteTuple() VertSpriteTuple {
-    return .{ Sprite8x16{}, Sprite8x32{}, Sprite16x32{}, Sprite32x64{} };
-}
-
 pub fn main() noreturn {
     LCD.setupDisplayControl(.{
         .mode = .Mode0, // No Affine BGs
@@ -42,49 +24,56 @@ pub fn main() noreturn {
 
     OAM.init();
 
-    const sprites = square_sprites;
-
-    sprites[0].load(); // Copy Mapping to VRAM and Palette to PALRAM
+    sprites[0][0].load(); // Copy Mapping to VRAM and Palette to PALRAM
 
     var sprite: *OAM.Attribute = OAM.allocate();
-    sprite.paletteMode = sprites[0].paletteMode();
+    sprite.paletteMode = sprites[0][0].paletteMode();
     sprite.palette = 0;
     sprite.tileIndex = 0;
-    sprite.setSize(sprites[0].size());
+    sprite.setSize(sprites[0][0].size());
 
     var x: i32 = 96;
     var y: i32 = 32;
 
     var i: i32 = 0;
+    var ii: u2 = 0;
 
     while (true) {
         LCD.naiveVSync();
         Input.readInput();
 
         const shoulder = Input.getShoulderJustPressed();
-        if (shoulder != 0) {
-            i = (i + shoulder) & 0b11;
 
-            // Index must be comptime known unfortunately
-            // so we need this ugly switch statement
-            switch (i) {
-                0 => {
-                    sprites[0].load();
-                    sprite.setSize(sprites[0].size());
+        if (Input.isKeyJustPressed(Input.Keys.A)) ii +%= 1;
+        if (Input.isKeyJustPressed(Input.Keys.B)) ii -%= 1;
+
+        if (shoulder != 0 or Input.isKeyJustPressed(Input.Keys.A | Input.Keys.B)) {
+            i = (i + shoulder) & 0b11;
+            ii %= 3;
+
+            switch (ii) {
+                0 => switch (i) {
+                    0 => loadSprite(0, 0, sprite),
+                    1 => loadSprite(0, 1, sprite),
+                    2 => loadSprite(0, 2, sprite),
+                    3 => loadSprite(0, 3, sprite),
+                    else => unreachable,
                 },
-                1 => {
-                    sprites[1].load();
-                    sprite.setSize(sprites[1].size());
+                1 => switch (i) {
+                    0 => loadSprite(1, 0, sprite),
+                    1 => loadSprite(1, 1, sprite),
+                    2 => loadSprite(1, 2, sprite),
+                    3 => loadSprite(1, 3, sprite),
+                    else => unreachable,
                 },
-                2 => {
-                    sprites[2].load();
-                    sprite.setSize(sprites[2].size());
+                2 => switch (i) {
+                    0 => loadSprite(2, 0, sprite),
+                    1 => loadSprite(2, 1, sprite),
+                    2 => loadSprite(2, 2, sprite),
+                    3 => loadSprite(2, 3, sprite),
+                    else => unreachable,
                 },
-                3 => {
-                    sprites[3].load();
-                    sprite.setSize(sprites[3].size());
-                },
-                else => unreachable,
+                else => {},
             }
         }
 
@@ -723,3 +712,24 @@ const Sprite32x64 = struct {
         GBA.memcpy32(GBA.OBJ_PALETTE_RAM, &Self.pal, Self.pal.len * @sizeOf(u32));
     }
 };
+
+fn initSpriteTupleTuple() SpriteTupleTuple {
+    return .{ initSquareSpriteTuple(), initHorizSpriteTuple(), initVertSpriteTuple() };
+}
+
+fn initSquareSpriteTuple() SquareSpriteTuple {
+    return .{ Sprite8x8{}, Sprite16x16{}, Sprite32x32{}, Sprite64x64{} };
+}
+
+fn initHorizSpriteTuple() HorizSpriteTuple {
+    return .{ Sprite16x8{}, Sprite32x8{}, Sprite32x16{}, Sprite64x32{} };
+}
+
+fn initVertSpriteTuple() VertSpriteTuple {
+    return .{ Sprite8x16{}, Sprite8x32{}, Sprite16x32{}, Sprite32x64{} };
+}
+
+fn loadSprite(comptime kind: usize, comptime i: usize, sprite: *OAM.Attribute) void {
+    sprites[kind][i].load();
+    sprite.setSize(sprites[kind][i].size());
+}