From http://www.jwz.org/xscreensaver/xscreensaver-5.38.tar.gz

[xscreensaver] / hacks / glx / boing.c

diff --git a/hacks/glx/boing.c b/hacks/glx/boing.c
index 0ba3d913199c0d93a516ff940c5305ffb02c23e4..55a05f3d4c67a98c94bdc50b832e9e62a5bdcb46 100644 (file)
--- a/hacks/glx/boing.c
+++ b/hacks/glx/boing.c
@@ -25,7 +25,7 @@
                        "*showFPS:      False            \n" \
                        "*wireframe:    False            \n" \
 
-# define refresh_boing 0
+# define free_boing 0
 # define release_boing 0
 #undef countof
 #define countof(x) (sizeof((x))/sizeof((*x)))
@@ -62,6 +62,8 @@ typedef struct {
   trackball_state *trackball;
   Bool button_down_p;
 
+  GLfloat speed;
+
   GLuint ball_list;
   double ball_x,   ball_y,   ball_z,   ball_th;
   double ball_dx,  ball_dy,  ball_dz,  ball_dth;
@@ -429,10 +431,10 @@ tick_physics (ModeInfo *mi)
   bp->ball_x  += bp->ball_dx;
   if      (bp->ball_x < min) bp->ball_x = min, bp->ball_dx = -bp->ball_dx,
     bp->ball_dth = -bp->ball_dth,
-    bp->ball_dx += (frand(speed/2) - speed);
+    bp->ball_dx += (frand(bp->speed/2) - bp->speed);
   else if (bp->ball_x > max) bp->ball_x = max, bp->ball_dx = -bp->ball_dx,
     bp->ball_dth = -bp->ball_dth,
-    bp->ball_dx += (frand(speed/2) - speed);
+    bp->ball_dx += (frand(bp->speed/2) - bp->speed);
 
   bp->ball_dy += bp->ball_ddy;
   bp->ball_y  += bp->ball_dy;
@@ -453,11 +455,18 @@ ENTRYPOINT void
 reshape_boing (ModeInfo *mi, int width, int height)
 {
   GLfloat h = (GLfloat) height / (GLfloat) width;
+  int y = 0;
 
   h *= 4.0 / 3.0;   /* Back in the caveman days we couldn't even afford
                        square pixels! */
 
-  glViewport (0, 0, (GLint) width, (GLint) height);
+  if (width > height * 5) {   /* tiny window: show middle */
+    height = width * 3/4;
+    y = -height/2;
+    h = height / (GLfloat) width;
+  }
+
+  glViewport (0, y, (GLint) width, (GLint) height);
 
   glMatrixMode(GL_PROJECTION);
   glLoadIdentity();
@@ -500,14 +509,7 @@ init_boing (ModeInfo *mi)
   boing_configuration *bp;
   int wire = MI_IS_WIREFRAME(mi);
 
-  if (!bps) {
-    bps = (boing_configuration *)
-      calloc (MI_NUM_SCREENS(mi), sizeof (boing_configuration));
-    if (!bps) {
-      fprintf(stderr, "%s: out of memory\n", progname);
-      exit(1);
-    }
-  }
+  MI_INIT (mi, bps);
 
   bp = &bps[MI_SCREEN(mi)];
 
@@ -568,16 +570,16 @@ init_boing (ModeInfo *mi)
 
   glBlendFunc (GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
 
-  speed = speed / 800.0;
+  bp->speed = speed / 800.0;
 
-  bp->ball_dth = (spin ? -speed * 7 * 360 : 0);
+  bp->ball_dth = (spin ? -bp->speed * 7 * 360 : 0);
 
   bp->ball_x   = 0.5 - ((ball_size/2) + frand(1-ball_size));
   bp->ball_y   = 0.2;
-  bp->ball_dx  = speed * 6 + frand(speed);
-  bp->ball_ddy = -speed;
+  bp->ball_dx  = bp->speed * 6 + frand(bp->speed);
+  bp->ball_ddy = -bp->speed;
 
-  bp->ball_dz  = speed * 6 + frand(speed);
+  bp->ball_dz  = bp->speed * 6 + frand(bp->speed);
 
   bp->trackball = gltrackball_init (False);
 }