git.y1.nz

commit 4d647100c7970df59d0547a8261304f76244ab75
parent ea41a0a07bfea80806d996b3c79a5b6d6be55a31
Author: Toxa <untoxa@mail.ru>
Date:   Fri,  8 Mar 2024 19:55:21 +0300

SMS/GG: support SHOW_SPRITES/HIDE_SPRITES macros (no hiding midframe)

Diffstat:
M
gbdk-lib/include/sms/sms.h
10
++++++----
M
gbdk-lib/libc/targets/z80/gg/crt0.s
3
+++
M
gbdk-lib/libc/targets/z80/sms/crt0.s
3
+++
M
gbdk-lib/libc/targets/z80/sms_int.s
45
++++++++++++++++++++++++++++++---------------

4 files changed, 42 insertions(+), 19 deletions(-)
diff --git a/gbdk-lib/include/sms/sms.h b/gbdk-lib/include/sms/sms.h
@@ -290,14 +290,14 @@ void refresh_OAM(void);
 #define HIDE_WIN
 
 /** Turns on the sprites layer.
-    Not yet implemented
 */
-#define SHOW_SPRITES
+#define SHOW_SPRITES \
+    (_sprites_OFF = 0)
 
 /** Turns off the sprites layer.
-    Not yet implemented
 */
-#define HIDE_SPRITES
+#define HIDE_SPRITES \
+    (_sprites_OFF = 1)
 
 /** Sets sprite size to 8x16 pixels, two tiles one above the other.
 */
@@ -710,6 +710,8 @@ extern volatile uint8_t _shadow_OAM_base;
 */
 extern volatile uint8_t _shadow_OAM_OFF;
 
+extern volatile uint8_t _sprites_OFF;
+
 /** Disable shadow OAM to VRAM copy on each VBlank
 */
 #define DISABLE_VBL_TRANSFER \
diff --git a/gbdk-lib/libc/targets/z80/gg/crt0.s b/gbdk-lib/libc/targets/z80/gg/crt0.s
@@ -248,6 +248,8 @@ __shadow_OAM_base::
         .ds     0x01
 __shadow_OAM_OFF::
         .ds     0x01
+__sprites_OFF::
+        .ds     0x01
 .mode::
         .ds     0x01            ; Current mode
 
@@ -269,4 +271,5 @@ __shadow_OAM_OFF::
         .db 0                   ; _VDP_ATTR_SHIFT
         .db #>_shadow_OAM       ; __shadow_OAM_base
         .db 0                   ; __shadow_OAM_OFF
+        .db 0                   ; __sprites_OFF
         .db .T_MODE_INOUT       ; .mode
 
diff --git a/gbdk-lib/libc/targets/z80/sms/crt0.s b/gbdk-lib/libc/targets/z80/sms/crt0.s
@@ -255,6 +255,8 @@ __shadow_OAM_base::
         .ds     0x01
 __shadow_OAM_OFF::
         .ds     0x01
+__sprites_OFF::
+        .ds     0x01
 .mode::
         .ds     0x01            ; Current mode
 
@@ -276,4 +278,5 @@ __shadow_OAM_OFF::
         .db 0                   ; _VDP_ATTR_SHIFT
         .db #>_shadow_OAM       ; __shadow_OAM_base
         .db 0                   ; __shadow_OAM_OFF
+        .db 0                   ; __sprites_OFF
         .db .T_MODE_INOUT       ; .mode
 
diff --git a/gbdk-lib/libc/targets/z80/sms_int.s b/gbdk-lib/libc/targets/z80/sms_int.s
@@ -21,28 +21,26 @@ _INT_ISR::
         jp z, 2$
         ;; handle VBlank
 
-        ld hl, (.sys_time)
-        inc hl
-        ld (.sys_time), hl
-
-        ld a, #1
-        ld (.vbl_done), a
-
         ;; transfer shadow OAM
         ld a, (__shadow_OAM_OFF)        ; check transfer is OFF
         or a
         jp nz, 1$
-        ld hl, #__shadow_OAM_base
-        ld h, (hl)
-        ld l, a                         ; a == 0 here
-        or h
-        jp z, 1$
 
         ld a, (_shadow_VDP_R5)
         srl a
-        ld d, a
+        ld d, a                         ; d == high byte of SAT address
         ld c, #.VDP_CMD
-        xor a
+
+        ld a, (__sprites_OFF)
+        or a
+        jp nz, 4$
+
+        ld hl, #__shadow_OAM_base
+        ld h, (hl)
+        ld l, a
+        cp h
+        jp z, 1$
+
         out (c), a
         out (c), d
         dec c                           ; c == .VDP_DATA
@@ -53,7 +51,23 @@ _INT_ISR::
         out (c), d
         dec c                           ; c == .VDP_DATA
         call .OUTI128
+        jp 1$
+4$:
+        xor a
+        out (c), a
+        out (c), d
+        dec c                           ; c == .VDP_DATA
+        ld a, #0xd0                     ; disable sprites
+        out (c), a
 1$:
+        ;; tick time
+        ld hl, (.sys_time)
+        inc hl
+        ld (.sys_time), hl
+
+        ;; set VBlank done flag
+        ld a, #1
+        ld (.vbl_done), a
 
         ;; call user-defined VBlank handlers
         ld hl, (.VBLANK_HANDLER0)
@@ -75,8 +89,9 @@ _INT_ISR::
         CALL_HL
         jp 3$
 
-        ;; handle HBlank
 2$:
+        ;; handle HBlank
+
         ld hl, (.HBLANK_HANDLER0)
         CALL_HL
 

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