From 914ee14327f54b8ec88b861e8dc08090d7041acf Mon Sep 17 00:00:00 2001
From: Bad Diode <bd@badd10de.dev>
Date: Sun, 18 Apr 2021 15:07:51 +0200
Subject: Fix rendering issue by hiding the sprites on initialization

---
 src/main.c | 38 ++++++++++++++++++++++----------------
 1 file changed, 22 insertions(+), 16 deletions(-)

diff --git a/src/main.c b/src/main.c
index 07c809e..a6385b3 100644
--- a/src/main.c
+++ b/src/main.c
@@ -429,11 +429,21 @@ int main(void) {
 
     // 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;
+    size_t n_tiles = 8;
+    u32 colors[] = {
+        0x11111111,
+        0x22222222,
+        0x33333333,
+        0x44444444,
+        0x55555555,
+        0x66666666,
+        0x77777777,
+        0x88888888,
+    };
+    for (size_t j = 0; j < n_tiles; ++j) {
+        for (size_t i = j * 8; i < 8 + 8 * j; ++i) {
+            tile_mem->data[i] = colors[j];
+        }
     }
 
     // Add colors to the sprite color palette. Tiles with color number 0 are
@@ -443,7 +453,7 @@ int main(void) {
     PAL_BUFFER_SPRITES[3] = COLOR_CYAN;
     PAL_BUFFER_SPRITES[4] = COLOR_GREY;
     PAL_BUFFER_SPRITES[5] = COLOR_BLACK;
-    PAL_BUFFER_SPRITES[15] = COLOR_RED;
+    PAL_BUFFER_SPRITES[6] = COLOR_RED;
 
     int x_a = 100;
     int y_a = 100;
@@ -452,6 +462,12 @@ int main(void) {
     int y_b = 50;
     int tile_id_b = 1;
 
+    // Initialize all attributes by disabling rendering. If we don't do this,
+    // glitches may appear.
+    for (size_t i = 0; i < 128; ++i) {
+        OBJ_ATTR_0(i) = (1 << 9);
+    }
+
     OBJ_ATTR_0(0) = y_a;
     OBJ_ATTR_1(0) = x_a;
     OBJ_ATTR_2(0) = tile_id_a;
@@ -460,16 +476,6 @@ int main(void) {
     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;
     int active_sprite = 0;
     while(true) {
-- 
cgit v1.2.1