Cleaned the interrupt code a bit

src/interrupts.c

@@ -0,0 +1,20 @@
+/**
+ * Copyright (c) 2022 Dominic Masters
+ * 
+ * This software is released under the MIT License.
+ * https://opensource.org/licenses/MIT
+ */
+
+#include "interrupts.h"
+
+void interruptOnScanline() {
+  if(LYC_REG == 0) {
+    LCDC_REG |= LCDCF_BG8000;
+    if((TEXTBOX_STATE & TEXTBOX_STATE_VISIBLE) != 0) {
+      LYC_REG = INTERRUPT_TEXTBOX_VRAM;
+    }
+  } else if(LYC_REG == INTERRUPT_TEXTBOX_VRAM) {
+    LCDC_REG &= ~LCDCF_BG8000;
+    LYC_REG = 0;
+  }
+}

src/interrupts.h

@@ -0,0 +1,14 @@
+/**
+ * Copyright (c) 2022 Dominic Masters
+ * 
+ * This software is released under the MIT License.
+ * https://opensource.org/licenses/MIT
+ */
+
+#pragma once
+#include "libs.h"
+#include "conversation/textbox.h"
+
+#define INTERRUPT_TEXTBOX_VRAM ((TEXTBOX_WIN_Y * TILE_HEIGHT) - 1)
+
+void interruptOnScanline();

src/main.c

@@ -7,18 +7,6 @@
 
 #include "main.h"
 
-#define TEXTBOX_INTERRUPT_Y ((TEXTBOX_WIN_Y * TILE_HEIGHT) - 1)
-
-// TODO: cleanup
-void scanline_isr() {
-  if(LYC_REG == 0) {
-    LYC_REG = TEXTBOX_INTERRUPT_Y;
-    LCDC_REG |= LCDCF_BG8000;
-  } else if(LYC_REG == TEXTBOX_INTERRUPT_Y) {
-    LYC_REG = 0;
-    LCDC_REG &= ~LCDCF_BG8000;
-  }
-}
 
 void main() {
   int16_t j;
@@ -27,14 +15,13 @@ void main() {
   // Set up the GAMEBOY's registers.
   disable_interrupts();
 
-  // Create a critical section
+  // Create a critical section for some video stuff
   CRITICAL {
     DISPLAY_OFF;
     LCDC_REG = LCDCF_OFF | LCDCF_BG8000 | LCDCF_BG9800 | LCDCF_BGON;
     STAT_REG |= STATF_LYC;
     LYC_REG = 0;
-
-    add_LCD(scanline_isr);
+    add_LCD(interruptOnScanline);
   }
   set_interrupts(VBL_IFLAG | LCD_IFLAG);
 
@@ -98,5 +85,6 @@ void main() {
     // Update conversation fade effect
     conversationFadeUpdate();
     // mainDebugDraw();
+    LCDC_REG |= LCDCF_BG8000;
   }
 }

src/main.h

@@ -9,9 +9,7 @@
 
 #include "libs.h"
 #include "time.h"
-
 #include "SM.h"
-
 #include "poker/poker.h"
 #include "poker/card.h"
 #include "conversation/fade.h"
@@ -19,7 +17,7 @@
 #include "conversation/queue.h"
 #include "conversation/textbox.h"
 #include "conversation/questionbox.h"
-
+#include "interrupts.h"
 #include "sprites/spritecards.h"
 
 #define GB_BACKGROUND_COLUMNS 0x20