Make use of the video memory dirty bit

src/display.c

@@ -778,28 +778,76 @@ static void (*_textpage_plotter(uint32_t currswitches, uint32_t txtflags))(uint1
     return plotFn;
 }
 
+static inline drawpage_mode_t _currentMainMode(uint32_t currswitches) {
+    if (currswitches & SS_TEXT) {
+        return DRAWPAGE_TEXT;
+    } else  {
+        if (currswitches & SS_HIRES) {
+            return DRAWPAGE_HIRES;
+        } else {
+            return DRAWPAGE_TEXT; // (LORES)
+        }
+    }
+}
+
+static inline drawpage_mode_t _currentMixedMode(uint32_t currswitches) {
+    if (currswitches & (SS_TEXT|SS_MIXED)) {
+        return DRAWPAGE_TEXT;
+    } else {
+        if (currswitches & SS_HIRES) {
+            return DRAWPAGE_HIRES;
+        } else {
+            return DRAWPAGE_TEXT; // (LORES)
+        }
+    }
+}
+
 GLUE_C_WRITE(video__write_2e_text0)
 {
     base_textwrt[ea] = b;
-    video_setDirty(A2_DIRTY_FLAG);
+    drawpage_mode_t mode = _currentMainMode(softswitches);
+    if (mode == DRAWPAGE_HIRES) {
+        return;
+    }
+    if (!(softswitches & SS_PAGE2)) {
+        video_setDirty(A2_DIRTY_FLAG);
+    }
 }
 
 GLUE_C_WRITE(video__write_2e_text0_mixed)
 {
     base_textwrt[ea] = b;
-    video_setDirty(A2_DIRTY_FLAG);
+    drawpage_mode_t mode = _currentMixedMode(softswitches);
+    if (mode == DRAWPAGE_HIRES) {
+        return;
+    }
+    if (!(softswitches & SS_PAGE2)) {
+        video_setDirty(A2_DIRTY_FLAG);
+    }
 }
 
 GLUE_C_WRITE(video__write_2e_text1)
 {
     base_ramwrt[ea] = b;
-    video_setDirty(A2_DIRTY_FLAG);
+    drawpage_mode_t mode = _currentMainMode(softswitches);
+    if (mode == DRAWPAGE_HIRES) {
+        return;
+    }
+    if (softswitches & SS_PAGE2) {
+        video_setDirty(A2_DIRTY_FLAG);
+    }
 }
 
 GLUE_C_WRITE(video__write_2e_text1_mixed)
 {
     base_ramwrt[ea] = b;
-    video_setDirty(A2_DIRTY_FLAG);
+    drawpage_mode_t mode = _currentMixedMode(softswitches);
+    if (mode == DRAWPAGE_HIRES) {
+        return;
+    }
+    if (softswitches & SS_PAGE2) {
+        video_setDirty(A2_DIRTY_FLAG);
+    }
 }
 
 // ----------------------------------------------------------------------------
@@ -1037,49 +1085,97 @@ static void (*_hirespage_plotter(uint32_t currswitches))(uint16_t, int, int, boo
 GLUE_C_WRITE(video__write_2e_even0)
 {
     base_hgrwrt[ea] = b;
-    video_setDirty(A2_DIRTY_FLAG);
+    drawpage_mode_t mode = _currentMainMode(softswitches);
+    if (mode == DRAWPAGE_TEXT) {
+        return;
+    }
+    if (!(softswitches & SS_PAGE2)) {
+        video_setDirty(A2_DIRTY_FLAG);
+    }
 }
 
 GLUE_C_WRITE(video__write_2e_even0_mixed)
 {
     base_hgrwrt[ea] = b;
-    video_setDirty(A2_DIRTY_FLAG);
+    drawpage_mode_t mode = _currentMixedMode(softswitches);
+    if (mode == DRAWPAGE_TEXT) {
+        return;
+    }
+    if (!(softswitches & SS_PAGE2)) {
+        video_setDirty(A2_DIRTY_FLAG);
+    }
 }
 
 GLUE_C_WRITE(video__write_2e_odd0)
 {
     base_hgrwrt[ea] = b;
-    video_setDirty(A2_DIRTY_FLAG);
+    drawpage_mode_t mode = _currentMainMode(softswitches);
+    if (mode == DRAWPAGE_TEXT) {
+        return;
+    }
+    if (!(softswitches & SS_PAGE2)) {
+        video_setDirty(A2_DIRTY_FLAG);
+    }
 }
 
 GLUE_C_WRITE(video__write_2e_odd0_mixed)
 {
     base_hgrwrt[ea] = b;
-    video_setDirty(A2_DIRTY_FLAG);
+    drawpage_mode_t mode = _currentMixedMode(softswitches);
+    if (mode == DRAWPAGE_TEXT) {
+        return;
+    }
+    if (!(softswitches & SS_PAGE2)) {
+        video_setDirty(A2_DIRTY_FLAG);
+    }
 }
 
 GLUE_C_WRITE(video__write_2e_even1)
 {
     base_ramwrt[ea] = b;
-    video_setDirty(A2_DIRTY_FLAG);
+    drawpage_mode_t mode = _currentMainMode(softswitches);
+    if (mode == DRAWPAGE_TEXT) {
+        return;
+    }
+    if (softswitches & SS_PAGE2) {
+        video_setDirty(A2_DIRTY_FLAG);
+    }
 }
 
 GLUE_C_WRITE(video__write_2e_even1_mixed)
 {
     base_ramwrt[ea] = b;
-    video_setDirty(A2_DIRTY_FLAG);
+    drawpage_mode_t mode = _currentMixedMode(softswitches);
+    if (mode == DRAWPAGE_TEXT) {
+        return;
+    }
+    if (softswitches & SS_PAGE2) {
+        video_setDirty(A2_DIRTY_FLAG);
+    }
 }
 
 GLUE_C_WRITE(video__write_2e_odd1)
 {
     base_ramwrt[ea] = b;
-    video_setDirty(A2_DIRTY_FLAG);
+    drawpage_mode_t mode = _currentMainMode(softswitches);
+    if (mode == DRAWPAGE_TEXT) {
+        return;
+    }
+    if (softswitches & SS_PAGE2) {
+        video_setDirty(A2_DIRTY_FLAG);
+    }
 }
 
 GLUE_C_WRITE(video__write_2e_odd1_mixed)
 {
     base_ramwrt[ea] = b;
-    video_setDirty(A2_DIRTY_FLAG);
+    drawpage_mode_t mode = _currentMixedMode(softswitches);
+    if (mode == DRAWPAGE_TEXT) {
+        return;
+    }
+    if (softswitches & SS_PAGE2) {
+        video_setDirty(A2_DIRTY_FLAG);
+    }
 }
 
 // ----------------------------------------------------------------------------
@@ -1169,30 +1265,6 @@ bool video_loadState(StateHelper_s *helper) {
 
 // ----------------------------------------------------------------------------
 
-static inline drawpage_mode_t _currentMainMode(uint32_t currswitches) {
-    if (currswitches & SS_TEXT) {
-        return DRAWPAGE_TEXT;
-    } else  {
-        if (currswitches & SS_HIRES) {
-            return DRAWPAGE_HIRES;
-        } else {
-            return DRAWPAGE_TEXT; // (LORES)
-        }
-    }
-}
-
-static inline drawpage_mode_t _currentMixedMode(uint32_t currswitches) {
-    if (currswitches & (SS_TEXT|SS_MIXED)) {
-        return DRAWPAGE_TEXT;
-    } else {
-        if (currswitches & SS_HIRES) {
-            return DRAWPAGE_HIRES;
-        } else {
-            return DRAWPAGE_TEXT; // (LORES)
-        }
-    }
-}
-
 static inline void _currentPageAndBank(uint32_t currswitches, drawpage_mode_t mode, OUTPARM int *page, OUTPARM int *bank) {
     // UTAIIe : 5-25
     if (currswitches & SS_80STORE) {

src/video/glvideo.c

@@ -310,8 +310,6 @@ static void glvideo_render(void) {
     if (!cpu_isPaused()) {
         // check if a2 video memory is dirty
         unsigned long wasDirty = video_clearDirty(A2_DIRTY_FLAG);
-        wasDirty = 1;
-#warning HACK FIXME TODO ... always setting A2 video memory dirty bit for now ...
         if (wasDirty) {
             fb = video_scan();
         }

src/vm.c

@@ -159,9 +159,10 @@ GLUE_C_READ(iie_page2_on)
         }
     } else {
         softswitches |= SS_SCREEN;
-        video_setDirty(A2_DIRTY_FLAG);
     }
 
+    video_setDirty(A2_DIRTY_FLAG);
+
     return floating_bus();
 }
 
@@ -174,6 +175,7 @@ GLUE_C_READ(read_switch_graphics)
 {
     if (softswitches & SS_TEXT) {
         softswitches &= ~SS_TEXT;
+        video_setDirty(A2_DIRTY_FLAG);
     }
     return floating_bus();
 }
@@ -182,6 +184,7 @@ GLUE_C_READ(read_switch_text)
 {
     if (!(softswitches & SS_TEXT)) {
         softswitches |= SS_TEXT;
+        video_setDirty(A2_DIRTY_FLAG);
     }
     return floating_bus();
 }
@@ -195,6 +198,7 @@ GLUE_C_READ(read_switch_no_mixed)
 {
     if (softswitches & SS_MIXED) {
         softswitches &= ~SS_MIXED;
+        video_setDirty(A2_DIRTY_FLAG);
     }
     return floating_bus();
 }
@@ -203,6 +207,7 @@ GLUE_C_READ(read_switch_mixed)
 {
     if (!(softswitches & SS_MIXED)) {
         softswitches |= SS_MIXED;
+        video_setDirty(A2_DIRTY_FLAG);
     }
     return floating_bus();
 }
@@ -240,6 +245,8 @@ GLUE_C_READ(iie_hires_off)
         softswitches |= SS_HGRWRT;
     }
 
+    video_setDirty(A2_DIRTY_FLAG);
+
     return floating_bus();
 }
 
@@ -263,6 +270,8 @@ GLUE_C_READ(iie_hires_on)
         }
     }
 
+    video_setDirty(A2_DIRTY_FLAG);
+
     return floating_bus();
 }
 
@@ -536,9 +545,10 @@ GLUE_C_READ(iie_80store_off)
 
     if (softswitches & SS_PAGE2) {
         softswitches |= SS_SCREEN;
-        video_setDirty(A2_DIRTY_FLAG);
     }
 
+    video_setDirty(A2_DIRTY_FLAG);
+
     return floating_bus();
 }
 
@@ -601,6 +611,8 @@ GLUE_C_READ(iie_ramrd_main)
         base_hgrrd  = apple_ii_64k[0];
     }
 
+    video_setDirty(A2_DIRTY_FLAG);
+
     return floating_bus();
 }
 
@@ -624,6 +636,8 @@ GLUE_C_READ(iie_ramrd_aux)
         base_hgrrd  = apple_ii_64k[1];
     }
 
+    video_setDirty(A2_DIRTY_FLAG);
+
     return floating_bus();
 }
 
@@ -733,6 +747,7 @@ GLUE_C_READ(iie_80col_off)
     }
 
     softswitches &= ~SS_80COL;
+    video_setDirty(A2_DIRTY_FLAG);
 
     return floating_bus();
 }
@@ -744,6 +759,7 @@ GLUE_C_READ(iie_80col_on)
     }
 
     softswitches |= SS_80COL;
+    video_setDirty(A2_DIRTY_FLAG);
 
     return floating_bus();
 }
@@ -758,6 +774,7 @@ GLUE_C_READ(iie_altchar_off)
     if (softswitches & SS_ALTCHAR) {
         softswitches &= ~SS_ALTCHAR;
         video_loadfont(0x40,0x40,ucase_glyphs,3);
+        video_setDirty(A2_DIRTY_FLAG);
     }
     return floating_bus();
 }
@@ -768,6 +785,7 @@ GLUE_C_READ(iie_altchar_on)
         softswitches |= SS_ALTCHAR;
         video_loadfont(0x40,0x20,mousetext_glyphs,1);
         video_loadfont(0x60,0x20,lcase_glyphs,2);
+        video_setDirty(A2_DIRTY_FLAG);
     }
     return floating_bus();
 }
@@ -799,6 +817,7 @@ GLUE_C_READ(iie_dhires_on)
 {
     if (!(softswitches & SS_DHIRES)) {
         softswitches |= SS_DHIRES;
+        video_setDirty(A2_DIRTY_FLAG);
     }
     return floating_bus();
 }
@@ -807,6 +826,7 @@ GLUE_C_READ(iie_dhires_off)
 {
     if (softswitches & SS_DHIRES) {
         softswitches &= ~SS_DHIRES;
+        video_setDirty(A2_DIRTY_FLAG);
     }
     return floating_bus();
 }