1 files changed, 101 insertions, 0 deletions
diff --git a/src/cgame/cg_animation.c b/src/cgame/cg_animation.c
new file mode 100644
index 00000000..5295998e
--- /dev/null
+++ b/src/cgame/cg_animation.c
@@ -0,0 +1,101 @@
+/*
+ *  Portions Copyright (C) 2000-2001 Tim Angus
+ *
+ *  This program is free software; you can redistribute it and/or modify it
+ *  under the terms of the OSML - Open Source Modification License v1.0 as
+ *  described in the file COPYING which is distributed with this source
+ *  code.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
+ */
+
+#include "cg_local.h"
+
+/*
+===============
+CG_RunLerpFrame
+
+Sets cg.snap, cg.oldFrame, and cg.backlerp
+cg.time should be between oldFrameTime and frameTime after exit
+===============
+*/
+void CG_RunLerpFrame( lerpFrame_t *lf )
+{
+  int     f, numFrames;
+  animation_t *anim;
+
+  // debugging tool to get no animations
+  if( cg_animSpeed.integer == 0 )
+  {
+    lf->oldFrame = lf->frame = lf->backlerp = 0;
+    return;
+  }
+
+  // if we have passed the current frame, move it to
+  // oldFrame and calculate a new frame
+  if( cg.time >= lf->frameTime )
+  {
+    lf->oldFrame = lf->frame;
+    lf->oldFrameTime = lf->frameTime;
+
+    // get the next frame based on the animation
+    anim = lf->animation;
+    if( !anim->frameLerp )
+      return;   // shouldn't happen
+
+    if( cg.time < lf->animationTime )
+      lf->frameTime = lf->animationTime;    // initial lerp
+    else
+      lf->frameTime = lf->oldFrameTime + anim->frameLerp;
+
+    f = ( lf->frameTime - lf->animationTime ) / anim->frameLerp;
+    numFrames = anim->numFrames;
+    if( anim->flipflop )
+      numFrames *= 2;
+
+    if( f >= numFrames )
+    {
+      f -= numFrames;
+      if( anim->loopFrames )
+      {
+        f %= anim->loopFrames;
+        f += anim->numFrames - anim->loopFrames;
+      }
+      else
+      {
+        f = numFrames - 1;
+        // the animation is stuck at the end, so it
+        // can immediately transition to another sequence
+        lf->frameTime = cg.time;
+      }
+    }
+
+    if( anim->reversed )
+      lf->frame = anim->firstFrame + anim->numFrames - 1 - f;
+    else if( anim->flipflop && f >= anim->numFrames )
+      lf->frame = anim->firstFrame + anim->numFrames - 1 - ( f % anim->numFrames );
+    else
+      lf->frame = anim->firstFrame + f;
+
+    if( cg.time > lf->frameTime )
+    {
+      lf->frameTime = cg.time;
+      if( cg_debugAnim.integer )
+        CG_Printf( "Clamp lf->frameTime\n" );
+    }
+  }
+
+  if( lf->frameTime > cg.time + 200 )
+    lf->frameTime = cg.time;
+
+  if( lf->oldFrameTime > cg.time )
+    lf->oldFrameTime = cg.time;
+
+  // calculate current lerp value
+  if( lf->frameTime == lf->oldFrameTime )
+    lf->backlerp = 0;
+  else
+    lf->backlerp = 1.0 - (float)( cg.time - lf->oldFrameTime ) / ( lf->frameTime - lf->oldFrameTime );
+}