initial commit

2026-07-18 20:34:55 +02:00
commit 59ad004c96
474 changed files with 226635 additions and 0 deletions
@@ -0,0 +1,100 @@
+#include <string.h>
+#include <c64/vic.h>
+#include <c64/memmap.h>
+#include <conio.h>
+#include <fixmath.h>
+
+// Address of hires buffer and color buffers
+#define Screen	((char *)0xe000)
+#define Color	((char *)0xc800)
+#define Color2	((char *)0xd800)
+
+// Bit patterns for eight different color pairs
+char colors[] = {
+	0xff, 0xff, 
+	0xee, 0xbb,
+	0xaa, 0xaa,
+	0x88, 0x22,
+
+	0x44, 0x11,
+	0x55, 0x55,
+	0xdd, 0x77,
+	0x33, 0xcc
+};
+
+int main(void)
+{
+	// Install the IRQ trampoline
+	mmap_trampoline();
+
+	// Turn of the kernal ROM
+	mmap_set(MMAP_NO_ROM);
+
+	// Switch VIC into multicolor bitmap mode
+	vic_setmode(VICM_HIRES_MC, Color, Screen);
+
+	// Clear the screen and set the colors
+	vic.color_back = 0x00;
+
+	memset(Screen, 0, 8000);
+	memset(Color, 0x27, 1000);
+	memset(Color2, 0x03, 1000);
+
+	// Loop over all pixels
+	int	py, px;
+	
+	for(py=0; py<100; py++)
+	{
+		for(px=0; px<160; px++)
+		{
+			// Value in the complex plane
+
+//			int		xz = (int)(((float)px * (3.5 / 160.0) - 2.5) * 4096 + 0.5);
+//			int		yz = (int)(((float)py * (2.4 / 100.0) - 1.2) * 4096 + 0.5);
+			
+			int		xz = lmul8f8s(px, (int)((3.5 / 160.0) * 4096 * 256)) - (int)(2.5 * 4096);
+			int		yz = lmul8f8s(py, (int)((2.4 / 100.0) * 4096 * 256)) - (int)(1.2 * 4096);
+
+			// Iterate up to 32 times
+			int		x = 0, y = 0;
+			int		i;
+			for(i=0; i<32; i++)
+			{
+				unsigned long xq = lsqr4f12s(x), yq = lsqr4f12s(y);
+
+				if (xq + yq >= 0x04000000UL) break;
+				
+				int	xt = (int)(xq >> 12) - (int)(yq >> 12) + xz;		
+				y = 2 * lmul4f12s(x, y) + yz;
+				x = xt;
+			}
+		
+			if (i < 32)
+			{
+				// Position on screen
+				char	* dp = Screen + 320 * (py >> 2) + 2 * (py & 3) + 2 * (px & ~3);
+
+				// Mask of pixels to change
+				char	mask = 0xc0 >> (2 * (px & 3));
+
+				// Get the two color patterns for upper and lower half
+				char	c0 = colors[2 * (i & 7)], c1 = colors[2 * (i & 7) + 1];
+
+				// Put the pixels into the image
+				dp[0] |= c0 & mask;
+				dp[1] |= c1 & mask;
+			}
+		}
+	}
+
+	// Re-enable the kernal
+	mmap_set(MMAP_NO_BASIC);
+
+	// Wait for key press
+	getch();	
+
+	// Restore VIC state
+	vic_setmode(VICM_TEXT, (char *)0x0400, (char *)0x1000);
+
+	return 0;
+}