Add initial sprite tests

1 files changed, 129 insertions, 62 deletions

diff --git a/src/main.c b/src/main.c
index b09d54f..07c809e 100644
--- a/src/main.c
+++ b/src/main.c
@@ -25,23 +25,29 @@
 #define DISP_STATUS *((vu32*)(MEM_IO + 0x0004))
 #define DISP_VCOUNT *((vu32*)(MEM_IO + 0x0006))
 
-// Bits for display control.
-#define DISP_CTRL_PAGE (1 << 4)
-
-// Display modes.
-#define DISP_MODE_0 0x0000
-#define DISP_MODE_1 0x0001
-#define DISP_MODE_2 0x0002
-#define DISP_MODE_3 0x0003
-#define DISP_MODE_4 0x0004
-#define DISP_MODE_5 0x0005
-
-// Layers.
-#define DISP_BG_0 0x0100
-#define DISP_BG_1 0x0200
-#define DISP_BG_2 0x0400
-#define DISP_BG_3 0x0800
-#define DISP_OBJ  0x1000
+// The first three bits in the DISP_CTRL are used to control the video mode.
+#define DISP_MODE_0     0x0000
+#define DISP_MODE_1     0x0001
+#define DISP_MODE_2     0x0002
+#define DISP_MODE_3     0x0003
+#define DISP_MODE_4     0x0004
+#define DISP_MODE_5     0x0005
+#define DISP_GB         (1 << 3)
+#define DISP_PAGE       (1 << 4)
+#define DISP_OAM_HBLANK (1 << 5)
+#define DISP_OBJ_1D     (1 << 6)
+#define DISP_BLANK      (1 << 7)
+#define DISP_BG_0       (1 << 8)
+#define DISP_BG_1       (1 << 9)
+#define DISP_BG_2       (1 << 10)
+#define DISP_BG_3       (1 << 11)
+#define DISP_OBJ        (1 << 12)
+
+// Registers to control of BG layers.
+#define BG_CTRL_0 *((vu16*)(0x04000008 + 0x0000))
+#define BG_CTRL_1 *((vu16*)(0x04000008 + 0x0002))
+#define BG_CTRL_2 *((vu16*)(0x04000008 + 0x0004))
+#define BG_CTRL_3 *((vu16*)(0x04000008 + 0x0006))
 
 // Screen settings.
 #define SCREEN_WIDTH 240
@@ -51,6 +57,19 @@
 // (RGB) have a 0--31 range. For example, pure red would be rgb15(31, 0, 0).
 typedef u16 Color;
 
+//
+// Tile memory access.
+//
+
+// NOTE: Only defining 4bpp tiles for now.
+typedef struct Tile {
+    u32 data[8];
+} Tile;
+
+typedef Tile TileBlock[512];
+
+#define TILE_MEM ((TileBlock*) MEM_VRAM)
+
 // We can treat the screen as a HxW matrix. With the following macro we can
 // write a pixel to the screen at the (x, y) position using:
 //
@@ -59,7 +78,8 @@ typedef u16 Color;
 typedef Color Scanline[SCREEN_WIDTH];
 #define FRAMEBUFFER ((Scanline*)MEM_VRAM)
 #define SCREEN_BUFFER ((vu16*) MEM_VRAM)
-#define PAL_BUFFER ((vu16*) MEM_PAL)
+#define PAL_BUFFER_BG ((vu16*) MEM_PAL)
+#define PAL_BUFFER_SPRITES ((vu16*) 0x05000200)
 
 //
 // Colors.
@@ -271,7 +291,7 @@ draw_fill_rect_m4(int x0, int y0, int x1, int y1, u8 col_index, vu16 *buffer) {
 
 static inline void
 flip_page() {
-    DISP_CTRL ^= DISP_CTRL_PAGE;
+    DISP_CTRL ^= DISP_PAGE;
 }
 
 #define SCREEN_PAGE_1 ((vu16*) MEM_VRAM)
@@ -367,33 +387,8 @@ key_hold(u32 key) {
 // Check if the given key/button is currently pressed.
 #define KEY_PRESSED(key) (~(KEY_INPUTS) & key)
 
-int main(void) {
-    DISP_CTRL = DISP_MODE_3 | DISP_BG_2;
-
-    // Test setting OBJ parameters for sprite N with my custom macros.
-    OBJ_ATTR_0(0) = 0xBADD;
-    OBJ_ATTR_1(0) = 0x10DE;
-    OBJ_ATTR_2(0) = 0xAC1D;
-    OBJ_ATTR_0(1) = 0xFA7E;
-    OBJ_ATTR_1(1) = 0xD15E;
-    OBJ_ATTR_2(1) = 0xA5ED;
-    OBJ_ATTR_0(2) = 0xBADD;
-    OBJ_ATTR_1(2) = 0x10DE;
-    OBJ_ATTR_2(2) = 0xAC1D;
-    OBJ_ATTR_0(3) = 0xFA7E;
-    OBJ_ATTR_1(3) = 0xD15E;
-    OBJ_ATTR_2(3) = 0xA5ED;
-    OBJ_AFFINE_PA(0) = 0x0011;
-    OBJ_AFFINE_PB(0) = 0x2233;
-    OBJ_AFFINE_PC(0) = 0x4455;
-    OBJ_AFFINE_PD(0) = 0x6677;
-    OBJ_AFFINE_PA(1) = 0xAABB;
-    OBJ_AFFINE_PB(1) = 0xCCDD;
-    OBJ_AFFINE_PC(1) = 0xEEFF;
-    OBJ_AFFINE_PD(1) = 0x0101;
-
-    // draw_fill_rect(0, 0, SCREEN_WIDTH, SCREEN_HEIGHT, COLOR_GREY);
-
+void
+draw_logo() {
     int side = 60;
     int line = 35;
     int height = side * 0.5;
@@ -425,31 +420,103 @@ int main(void) {
     draw_line(x + height, y, x + height + line, y, COLOR_WHITE);
     draw_line(x - line, y + 1, x, y + 1, COLOR_WHITE);
     draw_line(x + height, y + 1, x + height + line, y + 1, COLOR_WHITE);
+}
+
+int main(void) {
+    // Configure the display in mode 0 to show OBJs, where tile memory is
+    // sequential.
+    DISP_CTRL = DISP_MODE_0 | DISP_OBJ | DISP_OBJ_1D;
+
+    // Create two 4bpp tiles, one filled with color 1 and another with color 2.
+    Tile *tile_mem = &TILE_MEM[4][0];
+    for (size_t i = 0; i < 8; ++i) {
+        tile_mem->data[i] = 0x11111111;
+    }
+    for (size_t i = 8; i < 16; ++i) {
+        tile_mem->data[i] = 0x22222222;
+    }
+
+    // Add colors to the sprite color palette. Tiles with color number 0 are
+    // treated as transparent.
+    PAL_BUFFER_SPRITES[1] = COLOR_WHITE;
+    PAL_BUFFER_SPRITES[2] = COLOR_RED;
+    PAL_BUFFER_SPRITES[3] = COLOR_CYAN;
+    PAL_BUFFER_SPRITES[4] = COLOR_GREY;
+    PAL_BUFFER_SPRITES[5] = COLOR_BLACK;
+    PAL_BUFFER_SPRITES[15] = COLOR_RED;
+
+    int x_a = 100;
+    int y_a = 100;
+    int tile_id_a = 0;
+    int x_b = 50;
+    int y_b = 50;
+    int tile_id_b = 1;
+
+    OBJ_ATTR_0(0) = y_a;
+    OBJ_ATTR_1(0) = x_a;
+    OBJ_ATTR_2(0) = tile_id_a;
+
+    OBJ_ATTR_0(1) = y_b;
+    OBJ_ATTR_1(1) = x_b;
+    OBJ_ATTR_2(1) = tile_id_b;
+
+    // for (size_t i = 0; i < 16; ++i) {
+    //     PAL_BUFFER_SPRITES[i] = COLOR_RED;
+    // }
+    // PAL_BUFFER_SPRITES[0] = COLOR_RED;
+    // PAL_BUFFER_BG[0] = COLOR_WHITE;
+
+    // for (size_t i = 0; i < sizeof(tile_mem->data); ++i) {
+    //     tile_mem->data[i] = COLOR_WHITE;
+    // }
+
     int frame_counter = 0;
-    bool toggle_key_down = false;
+    int active_sprite = 0;
     while(true) {
         wait_vsync();
-        if (frame_counter++ > 30) {
-            frame_counter = 0;
-        }
         poll_keys();
 
         // Toggle frame counter when we press down.
-        if (key_pressed(KEY_DOWN)) {
-            toggle_key_down ^= 1;
+        if (key_pressed(KEY_DOWN) || key_hold(KEY_DOWN)) {
+            if (active_sprite == 0) {
+                y_a += 3;
+            } else {
+                y_b += 3;
+            }
         }
-        if (toggle_key_down) {
-            put_text(8, 8, COLOR_GREY, "TOGGLE: OFF");
-            put_text(8, 8, COLOR_RED, "TOGGLE: ON");
-        } else {
-            put_text(8, 8, COLOR_GREY, "TOGGLE: ON");
-            put_text(8, 8, COLOR_RED, "TOGGLE: OFF");
+        if (key_pressed(KEY_UP) || key_hold(KEY_UP)) {
+            if (active_sprite == 0) {
+                y_a -= 3;
+            } else {
+                y_b -= 3;
+            }
+        }
+        if (key_pressed(KEY_LEFT) || key_hold(KEY_LEFT)) {
+            if (active_sprite == 0) {
+                x_a -= 3;
+            } else {
+                x_b -= 3;
+            }
         }
-        if (key_hold(KEY_DOWN)) {
-            put_text(8, 24, COLOR_RED, "HOLDING");
-        } else {
-            put_text(8, 24, COLOR_GREY, "HOLDING");
+        if (key_pressed(KEY_RIGHT) || key_hold(KEY_RIGHT)) {
+            if (active_sprite == 0) {
+                x_a += 3;
+            } else {
+                x_b += 3;
+            }
         }
+        if (key_pressed(KEY_B)) {
+            if (active_sprite == 0) {
+                active_sprite = 1;
+            } else {
+                active_sprite = 0;
+            }
+        }
+
+        OBJ_ATTR_0(0) = y_a & 0xFF;
+        OBJ_ATTR_1(0) = x_a & 0xFF;
+        OBJ_ATTR_0(1) = y_b & 0xFF;
+        OBJ_ATTR_1(1) = x_b & 0xFF;
     };
 
     return 0;