Hey there, I've been doing a bit of programming with QuickBasic using MS-DOS 6.22 running under QEMU 0.9.0/x86/Linux. It's all fine and dandy except for one (big) problem: sin() and cos() don't work correctly.
Here's a demonstration: http://nonlogic.org/dump/bin/1183539319-glitchy.exe It works fine on a real PC, and even VMWare, but not under QEMU. I'm pretty sure it's QEMU, as I don't have the problem running it under QBasic 1.0, which I hear *emulates* sin() and cos(). But, let's face it, compared with QuickBasic 4.5, QBasic 1.0 sucks. What happens under QEMU is, after drawing 1/8, it draws the third 1/8 when it should be drawing the second 1/8, and vice versa. Same goes with the sixth and seventh 1/8s. Here's the source code: CONST pi = 3.141592653589793# CONST p256 = pi / 128 SCREEN 13 FOR i = 0 TO 31 PALETTE 0 + i, i * &H10101 PALETTE 32 + i, i * &H2 PALETTE 64 + i, i * &H200 PALETTE 96 + i, i * &H202 PALETTE 128 + i, i * &H20000 PALETTE 160 + i, i * &H20002 PALETTE 192 + i, i * &H20200 PALETTE 224 + i, i * &H20202 NEXT FOR i = 0 TO 256 PSET (i, 0), i px = 160 + SIN(i * p256) * 80 py = 100 + -COS(i * p256) * 80 PSET (px, py), i t = TIMER DO: LOOP WHILE TIMER - t < .01 NEXT Note that it breaks with ANY use of sin() or cos() under QB4.5. --GreaseMonkey Send instant messages to your online friends http://au.messenger.yahoo.com
