Package: airstrike
Version: 0.99+1.0pre6a-3
Severity: important
There is a bug in the function that calculates collisions, when one of the
sprites has speed 0, it tries to do a division by zero (resulting in a nan).
This problem causes weird "out of playable window" sprites, making it unusable.
I could only reproduce this bug in amd64.
The patch attached fixes the problem.
-- System Information:
Debian Release: 4.0
APT prefers unstable
APT policy: (500, 'unstable'), (500, 'testing'), (1, 'experimental')
Architecture: amd64 (x86_64)
Shell: /bin/sh linked to /bin/bash
Kernel: Linux 2.6.18-3-amd64
Locale: LANG=es_AR.UTF-8, LC_CTYPE=es_AR.UTF-8 (charmap=UTF-8)
Versions of packages airstrike depends on:
ii airstrike-common 0.99+1.0pre6a-3 2d dogfight game in the tradition
ii libc6 2.3.6.ds1-10 GNU C Library: Shared libraries
ii libsdl-image1.2 1.2.5-2+b1 image loading library for Simple D
ii libsdl1.2debian 1.2.11-7 Simple DirectMedia Layer
airstrike recommends no packages.
-- no debconf information
diff -ruNa airstrike-0.99+1.0pre6a/src/mech.c
airstrike-0.99+1.0pre6a.new/src/mech.c
--- airstrike-0.99+1.0pre6a/src/mech.c 2003-01-18 16:48:05.000000000 -0300
+++ airstrike-0.99+1.0pre6a.new/src/mech.c 2007-01-14 16:04:06.000000000
-0300
@@ -335,11 +335,10 @@
n[2]*((mech_sprite_t *)s1)->ang_vel +
n[3]*((mech_sprite_t *)s2)->ang_vel;
- if (a > 0)
- {
- b = n[0]*delta[0] + n[1]*delta[1] + n[2]*delta[2]
+ b = n[0]*delta[0] + n[1]*delta[1] + n[2]*delta[2]
- n[0]*delta[3] - n[1]*delta[4] + n[3]*delta[5];
-
+ if ( (a > 0) && (abs(b) > 0) )
+ {
c = -1.4*a/b;
s1->vel[0] += c*delta[0];
@@ -479,10 +478,9 @@
a = n[0]*s1->vel[0] + n[1]*s1->vel[1] +
n[2]*((mech_sprite_t *)s1)->ang_vel;
- if (a > 0)
+ b = n[0]*delta[0] + n[1]*delta[1] + n[2]*delta[2];
+ if ( (a > 0) && (abs(b) > 0) )
{
- b = n[0]*delta[0] + n[1]*delta[1] + n[2]*delta[2];
-
c = -1.2*a/b;
s1->vel[0] += c*delta[0];
