Add fractal tree sample

README.md

@@ -586,6 +586,12 @@ The C64 has a hires graphics mode with 320x200 pixels.  Oscar provides a library
 
 Draws and clears lines with various patterns.
 
+#### Draw lines "fractaltree.c"
+
+Draws a recursive fractal tree.
+
+![Fractal recursive tree](samples/hires/fractaltree.png)
+
 #### Draw 3D wireframe "cube3d.c"
 
 Draws a rotating 3D wireframe cube using draw (OR) and clear (AND) operations.  The 3D operations are performed using 12.4 bit fixpoint math.

samples/hires/fractaltree.c

@@ -0,0 +1,64 @@
+#include <c64/memmap.h>
+#include <c64/vic.h>
+#include <gfx/bitmap.h>
+#include <math.h>
+#include <string.h>
+#include <conio.h>
+
+
+char *	const	Color = (char *)0xd000;
+char *	const	Hires =	(char *)0xe000;
+
+Bitmap		Screen;
+ClipRect	Clip = {0, 0, 320, 200};
+
+void init(void)
+{
+	mmap_trampoline();
+	mmap_set(MMAP_RAM);
+
+	memset(Color, 0x01, 1000);
+	memset(Hires, 0x00, 8000);
+
+	mmap_set(MMAP_NO_ROM);
+
+	vic_setmode(VICM_HIRES, Color, Hires);
+
+	vic.color_border = VCOL_WHITE;
+
+	bm_init(&Screen, Hires, 40, 25);	
+}
+
+void done(void)
+{
+	mmap_set(MMAP_ROM);
+
+	getch();
+
+	vic_setmode(VICM_TEXT, (char *)0x0400, (char *)0x1000);
+}
+
+void draw(float x, float y, float a, float s)
+{
+	if (s < 6.0)
+		return;
+
+	float	tx = x + cos(a) * s;
+	float	ty = y + sin(a) * s;
+
+	bm_line(&Screen, &Clip, x, y, tx, ty, 0xff, LINOP_SET);
+
+	draw(tx, ty, a + 0.3, s * 0.9);
+	draw(tx, ty, a - 0.4, s * 0.8);
+}
+
+int main(void)
+{
+	init();
+
+	draw(140, 199, PI * 1.5, 32);
+
+	done();
+	
+	return 0;
+}

samples/hires/func3d.c

@@ -8,6 +8,8 @@
 #include <gfx/bitmap.h>
 #include <stdio.h>
 
+#pragma stacksize(1024)
+
 #pragma region(main, 0x0a00, 0xc800, , , {code, data, bss, heap, stack} )
 
 

samples/hires/make.bat

@@ -4,3 +4,4 @@ call ..\..\bin\oscar64 lines.c -n
 call ..\..\bin\oscar64 polygon.c -n
 call ..\..\bin\oscar64 bitblit.c -n
 call ..\..\bin\oscar64 cube3d.c -n
+call ..\..\bin\oscar64 fractaltree.c -n

samples/memmap/allmem.c

@@ -4,6 +4,8 @@
 
 // make space until 0x1000 by for the stack
 
+#pragma stacksize(0x0600)
+
 #pragma region( stack, 0x0a00, 0x1000, , , {stack} )
 
 // everything beyond will be code, data, bss and heap to the end