From 3583aa29bc5da067f6aba88d6548bfbd00ac75d5 Mon Sep 17 00:00:00 2001
From: UnknownShadow200 <unknownshadow200@gmail.com>
Date: Fri, 2 Feb 2024 21:37:53 +1100
Subject: [PATCH] Dreamcast: Try to fix freeze/crash after leaving in-game and
 then trying to go in-game again

---
 src/Window_Dreamcast.c         | 29 ++++++++++++++++++-----------
 third_party/gldc/src/texture.c | 31 +++++++++++++------------------
 2 files changed, 31 insertions(+), 29 deletions(-)

diff --git a/src/Window_Dreamcast.c b/src/Window_Dreamcast.c
index 94ba5f9db..105fc0764 100644
--- a/src/Window_Dreamcast.c
+++ b/src/Window_Dreamcast.c
@@ -31,21 +31,19 @@ void Window_Init(void) {
 	Input.Sources = INPUT_SOURCE_GAMEPAD;
 	DisplayInfo.ContentOffsetX = 10;
 	DisplayInfo.ContentOffsetY = 20;
+	
+	vid_set_mode(DEFAULT_VID_MODE, DEFAULT_PIXEL_MODE);
+	vid_flip(0);
+	// TODO: Why doesn't 32 bit work on real hardware for in-game?
 }
 
 void Window_Free(void) { }
 
 void Window_Create2D(int width, int height) { 
 	launcherMode = true;
-	vid_set_mode(DEFAULT_VID_MODE, PM_RGB888);
-	vid_flip(0);
 }
-
 void Window_Create3D(int width, int height) { 
 	launcherMode = false;
-	vid_set_mode(DEFAULT_VID_MODE, DEFAULT_PIXEL_MODE);
-	vid_flip(0);
-	// TODO: Why doesn't 32 bit work on real hardware?
 }
 
 void Window_SetTitle(const cc_string* title) { }
@@ -234,21 +232,30 @@ void Window_UpdateRawMouse(void)  { }
 *------------------------------------------------------Framebuffer--------------------------------------------------------*
 *#########################################################################################################################*/
 static struct Bitmap fb_bmp;
+
 void Window_AllocFramebuffer(struct Bitmap* bmp) {
 	bmp->scan0 = (BitmapCol*)Mem_Alloc(bmp->width * bmp->height, 4, "window pixels");
 	fb_bmp = *bmp;
 }
 
 void Window_DrawFramebuffer(Rect2D r) {
-	// TODO probably bogus..
-	// TODO: Don't redraw everything
-	int size = fb_bmp.width * fb_bmp.height * 4;
-	
 	// TODO: double buffering ??
 	//	https://dcemulation.org/phpBB/viewtopic.php?t=99999
 	//	https://dcemulation.org/phpBB/viewtopic.php?t=43214
 	vid_waitvbl();
-	sq_cpy(vram_l, fb_bmp.scan0, size);
+	
+	for (int y = r.y; y < r.y + r.Height; y++)
+	{
+		BitmapCol* src = Bitmap_GetRow(&fb_bmp, y);
+		uint16_t*  dst = vram_s + vid_mode->width * y;
+		
+		for (int x = r.x; x < r.x + r.Width; x++)
+		{
+			BitmapCol color = src[x];
+			// 888 to 565 (discard least significant bits)
+			dst[x] = ((BitmapCol_R(color) & 0xF8) << 8) | ((BitmapCol_G(color) & 0xFC) << 3) | (BitmapCol_B(color) >> 3);
+		}
+	}
 }
 
 void Window_FreeFramebuffer(struct Bitmap* bmp) {
diff --git a/third_party/gldc/src/texture.c b/third_party/gldc/src/texture.c
index bc887d483..2fb3fd291 100644
--- a/third_party/gldc/src/texture.c
+++ b/third_party/gldc/src/texture.c
@@ -16,31 +16,30 @@ TextureObject* TEXTURE_ACTIVE = NULL;
 static TextureObject TEXTURE_LIST[MAX_TEXTURE_COUNT];
 static unsigned char TEXTURE_USED[MAX_TEXTURE_COUNT / 8];
 
-static char texture_id_map_used(unsigned int id) {
+static int texture_id_map_used(unsigned int id) {
     unsigned int i = id / 8;
     unsigned int j = id % 8;
 
-    unsigned char v = TEXTURE_USED[i] & (unsigned char) (1 << j);
-    return !!(v);
+    return TEXTURE_USED[i] & (unsigned char)(1 << j);
 }
 
 static void texture_id_map_reserve(unsigned int id) {
-    unsigned int j = (id % 8);
     unsigned int i = id / 8;
-
-    TEXTURE_USED[i] |= (unsigned char) 1 << j;
+    unsigned int j = id % 8;
+    TEXTURE_USED[i] |= (unsigned char)(1 << j);
 }
 
 static void texture_id_map_release(unsigned int id) {
     unsigned int i = id / 8;
     unsigned int j = id % 8;
-    TEXTURE_USED[i] &= (unsigned char) ~(1 << j);
+    TEXTURE_USED[i] &= (unsigned char)~(1 << j);
 }
 
 unsigned int texture_id_map_alloc(void) {
     unsigned int id;
     
-    for(id = 0; id < MAX_TEXTURE_COUNT; ++id) {
+    // ID 0 is reserved for default texture
+    for(id = 1; id < MAX_TEXTURE_COUNT; ++id) {
         if(!texture_id_map_used(id)) {
             texture_id_map_reserve(id);
             return id;
@@ -71,11 +70,11 @@ static void* yalloc_alloc_and_defrag(size_t size) {
 
 #define GL_KOS_INTERNAL_DEFAULT_MIPMAP_LOD_BIAS 4
 static void _glInitializeTextureObject(TextureObject* txr, unsigned int id) {
-    txr->index = id;
-    txr->width = txr->height = 0;
+    txr->index  = id;
+    txr->width  = txr->height = 0;
     txr->mipmap = 0;
-    txr->env = GPU_TXRENV_MODULATEALPHA;
-    txr->data = NULL;
+    txr->env    = GPU_TXRENV_MODULATEALPHA;
+    txr->data   = NULL;
     txr->minFilter = GL_NEAREST;
     txr->magFilter = GL_NEAREST;
     txr->mipmap_bias = GL_KOS_INTERNAL_DEFAULT_MIPMAP_LOD_BIAS;
@@ -83,8 +82,6 @@ static void _glInitializeTextureObject(TextureObject* txr, unsigned int id) {
 
 GLubyte _glInitTextures() {
     memset(TEXTURE_USED, 0, sizeof(TEXTURE_USED));
-    // Reserve zero so that it is never given to anyone as an ID!
-    texture_id_map_reserve(0);
 
     // Initialize zero as an actual texture object though because apparently it is!
     TextureObject* default_tex = &TEXTURE_LIST[0];
@@ -121,10 +118,8 @@ GLuint APIENTRY gldcGenTexture(void) {
 void APIENTRY gldcDeleteTexture(GLuint id) {
     TRACE();
 
-    if(id == 0) {
-        /* Zero is the "default texture" and we never allow deletion of it */
-        return;
-    }
+    if(id == 0) return;
+    /* Zero is the "default texture" and we never allow deletion of it */
 
     if(texture_id_map_used(id)) {
     	TextureObject* txr = &TEXTURE_LIST[id];