Universally use update method 2 for the lower screen and 0 for the upper screen. Method 1 causes problems after about 15 minutes; despite the double-buffering, screen updates start to tear in the middle consistently.

3 files changed, 17 insertions, 24 deletions

diff --git a/source/nds/draw.c b/source/nds/draw.c
index 9d1b8ec..2a9e440 100644
--- a/source/nds/draw.c
+++ b/source/nds/draw.c
@@ -811,7 +811,7 @@ u32 draw_yesno_dialog(enum SCREEN_ID screen, u32 sy, char *yes, char *no)
 //    draw_string_vcenter(screen_address, i+1, sy+1, box_width, COLOR_WHITE, no);
     draw_string_vcenter((unsigned short*)screen_addr, 138, 130, 58, COLOR_WHITE, no);
 
-	ds2_flipScreen(screen, 1);
+	ds2_flipScreen(screen, 2);
 
     gui_action_type gui_action = CURSOR_NONE;
     while((gui_action != CURSOR_SELECT)  && (gui_action != CURSOR_BACK))
@@ -860,7 +860,7 @@ void init_progress(enum SCREEN_ID screen, u32 total, char *text)
     drawboxfill((unsigned short*)screen_addr, progress_sx, progress_sy, progress_ex, 
 		progress_ey, COLOR16(15, 15, 15));
 
-	ds2_flipScreen(_progress_screen_id, 1);
+	ds2_flipScreen(_progress_screen_id, 2);
 }
 
 //	update progress bar
@@ -883,7 +883,7 @@ void update_progress(void)
 
 	drawboxfill(screen_addr, progress_sx, progress_sy, progress_sx+width, progress_ey, COLOR16(30, 19, 7));
 
-	ds2_flipScreen(_progress_screen_id, 1);
+	ds2_flipScreen(_progress_screen_id, 2);
 }
 
 //	display progress string
@@ -908,7 +908,7 @@ void show_progress(char *text)
 //  if (text[0] != '\0')
 //    print_string_center(progress_sy - 21, COLOR_PROGRESS_TEXT, COLOR_DIALOG, text);
 
-	ds2_flipScreen(_progress_screen_id, 1);
+	ds2_flipScreen(_progress_screen_id, 2);
 
 //  OSTimeDly(progress_wait);
 	mdelay(500);
diff --git a/source/nds/entry.cpp b/source/nds/entry.cpp
index ea5f6ce..ce8d732 100644
--- a/source/nds/entry.cpp
+++ b/source/nds/entry.cpp
@@ -174,7 +174,10 @@ bool8 S9xDeinitUpdate (int Width, int Height, bool8 /*sixteen_bit*/)
 			break;
 	}
 
-    ds2_flipScreen(UP_SCREEN, 1); // synchronise to vblank to avoid tearing
+    ds2_flipScreen(UP_SCREEN, 0);
+	// A problem with update method 1 (wait, double buffer) means that, after
+	// about 15 minutes of play time, the screen starts to half-redraw every
+	// frame. With update method 0, this is mitigated. (Method 2 is too slow.)
 
     return (TRUE);
 }
@@ -598,7 +601,6 @@ int sfc_main (int argc, char **argv)
 		if (Settings.Paused)
 		{
 			S9xSetSoundMute (TRUE);
-			// mdelay(50); // Delete this delay
 			unsigned short screen[256*192];
 
 			copy_screen((void*)screen, up_screen_addr, 0, 0, 256, 192);
diff --git a/source/nds/gui.c b/source/nds/gui.c
index 964944b..3438f62 100644
--- a/source/nds/gui.c
+++ b/source/nds/gui.c
@@ -1114,7 +1114,7 @@ s32 load_file(char **wildcards, char *result, char *default_dir_name)
 			}
 
 			redraw = 0;
-			ds2_flipScreen(DOWN_SCREEN, 2);		//not switch down screen buffer
+			ds2_flipScreen(DOWN_SCREEN, 2);
 		} //end if(0 != redraw)
 		else if(0 != redraw) {
 			unsigned int m, n;
@@ -1142,7 +1142,7 @@ s32 load_file(char **wildcards, char *result, char *default_dir_name)
 			}
 
 			draw_hscroll(m+1, redraw);
-			ds2_flipScreen(DOWN_SCREEN, 2);		//not switch down screen buffer
+			ds2_flipScreen(DOWN_SCREEN, 2);
 			redraw = 0;
 		}
 
@@ -1162,7 +1162,7 @@ s32 load_file(char **wildcards, char *result, char *default_dir_name)
 			{
 				if(draw_hscroll(0, 1) <= 1) path_scroll = 0x8000; //scroll left
 			}
-			ds2_flipScreen(DOWN_SCREEN, 2);		//not switch down screen buffer
+			ds2_flipScreen(DOWN_SCREEN, 2);
 		}
 
 		mdelay(50);			//about 50ms
@@ -1176,7 +1176,7 @@ s32 load_file(char **wildcards, char *result, char *default_dir_name)
 	manage_filelist_info(&filelist_info, -1);
 
 	ds2_clearScreen(DOWN_SCREEN, COLOR_BLACK);
-	ds2_flipScreen(DOWN_SCREEN, 2);				//not switch down screen buffer
+	ds2_flipScreen(DOWN_SCREEN, 2);
 
 	return return_value;
 }
@@ -3991,22 +3991,14 @@ u32 menu(u16 *screen)
 		save_game_config_file();
 	}
 	save_emu_config_file();
-	// mdelay(100); // Delete this delay
 	set_cpu_clock(clock_speed_number);
-	// mdelay(200); // Delete this delay
 	
-	ds2_clearScreen(DUAL_SCREEN, 0);
-	ds2_flipScreen(DUAL_SCREEN, 1);
+	ds2_clearScreen(DOWN_SCREEN, 0);
+	ds2_flipScreen(DOWN_SCREEN, 1);
 	copy_screen(up_screen_addr, (void*) screen, 0, 0, 256, 192);
-	ds2_flipScreen(UP_SCREEN, 1); // Flip again because otherwise it flickers
+	ds2_flipScreen(UP_SCREEN, 0);
 	ds2_setBacklight(2);
 
-//save game config
-//	save_game_config_file();
-//	save_emu_config_file();
-
-
-//	ds2_setCPUclocklevel(12);
 	wait_Allkey_release(0);
 
 	return return_value;
@@ -4722,7 +4714,7 @@ void gui_init(u32 lang_id)
     }
 
 	show_log(down_screen_addr);
-	ds2_flipScreen(DOWN_SCREEN, 1);
+	ds2_flipScreen(DOWN_SCREEN, 2);
 
 	flag = icon_init(lang_id);
 	if(0 != flag)
@@ -4758,8 +4750,7 @@ void gui_init(u32 lang_id)
 	return;
 
 gui_init_err:
-	ds2_flipScreen(DOWN_SCREEN, 1);
+	ds2_flipScreen(DOWN_SCREEN, 2);
 	wait_Anykey_press(0);
 	quit();
-	while(1);
 }