From fe180c8df4f656dc788af4d478dbbb53c0e5253b Mon Sep 17 00:00:00 2001
From: alekseiplusplus <alekseijeaves@protonmail.com>
Date: Sun, 3 Dec 2023 12:29:23 +1100
Subject: video part no longer segfaults

---
 src/video/ncurses.c | 42 +++++++++++++++++-------------------------
 1 file changed, 17 insertions(+), 25 deletions(-)

(limited to 'src/video')

diff --git a/src/video/ncurses.c b/src/video/ncurses.c
index 242a3e1..8e80580 100644
--- a/src/video/ncurses.c
+++ b/src/video/ncurses.c
@@ -14,11 +14,11 @@ int TermY = 0;
 WINDOW *AppleWindow;
 
 
-const byte* VRAM;
+byte* VRAM;
 
-byte* VRAM_Position;
+int vPosition = 0;
 
-int VRAM_Offset;
+int vOffset = 0;
 
 
 void PrintInfo()
@@ -82,8 +82,6 @@ void DisplayInit()
 
 	// Initialize the terminal shift register variables.
     VRAM = (byte*)malloc(960);
-    VRAM_Position = VRAM;
-    VRAM_Offset = 0;
 
     refresh();
 }
@@ -111,9 +109,9 @@ void DisplayInput(byte n)
 	if (n == CR) {
 		// Add spacing characters into VRAM
 		do {
-			*VRAM_Position = ' ';
-			VRAM_Position++;
-		} while (((int)(VRAM_Position - VRAM) % 40) > 0);
+			VRAM[vPosition] = ' ';
+			vPosition++;
+		} while ((vPosition % 40) > 0);
 
 		// Set display to next line
 		TermX = 0;
@@ -124,8 +122,8 @@ void DisplayInput(byte n)
 		mvwaddch(AppleWindow, TermY, TermX, n & 0x7F);
 	
 		// Add character to VRAM
-		*VRAM_Position = n & 0x7f;
-		VRAM_Position++;
+		VRAM[vPosition] = n & 0x7f;
+		vPosition++;
 
 		// Set display to next character/next line
 		TermX++;
@@ -136,31 +134,25 @@ void DisplayInput(byte n)
 	}
 
 	// Reset VRAM_Position if it's value is too great.
-	if (VRAM_Position >= (VRAM + 960))
-        VRAM_Position -= 960;
+	if (vPosition >= 960)
+        vPosition -= 960;
     
 	// If Y is past height..
     if (TermY >= 24) {
 		
 		//.. discard the first line..
-		VRAM_Offset += 40;
-		//.. verify the register offset..
-		if (VRAM_Offset >= 960)
-            VRAM_Offset = VRAM;
+		vOffset += 40;
 
-		//.. and create an offset variable to cycle through memory with.
-        byte *offset = VRAM + VRAM_Offset;
-
-        // Then, for every cell of the screen, fill with the contents of the video memory.
+        //.. then, for every cell of the screen except the last line, fill with VRAM..
         for (int i = 0; i < 23; i++) {
         for (int j = 0; j < 40; j++) {
-            if (offset >= (VRAM + 960))
-                offset -= 960;
-            mvwaddch(AppleWindow, i, j, *offset );
-            offset++;
+            mvwaddch(AppleWindow, i, j, VRAM[vOffset++ % 960] );
         }}
+
+		// ..and move offset up to next line.
+		vOffset += 40;
 		
-		// Set to start of final line, and clear line.
+		// Visually set to start of final line, and clear line.
         TermY = 23;
         TermX = 0;
         mvwprintw(AppleWindow, TermY, TermX,
-- 
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