Revert "MD3: Reuse state of last frame if animation didn't change"

This reverts commit c43cd9e.

but keeps the clamping of the frame numbers

caching doesn't work like this: The idRenderModelMD3 is shared between
multiple instances, so lastFrame, lastOldFrame and lastBackLerp would
have to be saved in staticModel/cachedModel or the renderEntity_s
otherwise animations don't work when there's more than one MD3 model of
a kind in the level.

refs dhewm#727 - still doesn't fix the animation speed issues mentioned
there, they are caused by "Recalculate gameLocal.msec each frame so
 60 frames add up to 1000ms" (sys.waitFrame() in scripts waits for
gameLocal.msec but that's the length of the current frame, not the next,
so when sleeping for 17ms and the next frame is a 16ms frame one might
sleep for two frames instead of one)

Author: DanielGibson

neo/renderer/Model_local.h

@@ -231,10 +231,6 @@ class idRenderModelMD3 : public idRenderModelStatic {
 	int							dataSize;		// just for listing purposes
 	struct md3Header_s *		md3;			// only if type == MOD_MESH
 	int							numLods;
-
-	int							lastFrame;
-	int							lastOldFrame;
-	float						lastBackLerp;
 	idList<const idMaterial*>	shaders;		// DG: md3Shader_t::shaderIndex indexes into this array
 
 	// DG: added the following so we can generate/store sil edges for shadows

neo/renderer/Model_md3.cpp

@@ -39,8 +39,7 @@ If you have questions concerning this license or the applicable additional terms
 ***********************************************************************/
 
 // DG: added constructor to make sure all members are initialized
-idRenderModelMD3::idRenderModelMD3() : index(-1), dataSize(0), md3(NULL), numLods(0),
-	lastFrame(-1), lastOldFrame(0), lastBackLerp(0.0f)
+idRenderModelMD3::idRenderModelMD3() : index(-1), dataSize(0), md3(NULL), numLods(0)
 {}
 
 // DG: added destructor to clean up the newly added silInfos (and md3 which used to leak)
@@ -329,21 +328,10 @@ idRenderModel *idRenderModelMD3::InstantiateDynamicModel( const struct renderEnt
 	backlerp = ent->shaderParms[SHADERPARM_MD3_BACKLERP];
 
 	if ( cachedModel ) {
-		if ( !r_useCachedDynamicModels.GetBool() || frame != lastFrame
-		     || oldframe != lastOldFrame || backlerp != lastBackLerp ) {
-			delete cachedModel;
-			cachedModel = NULL;
-		} else {
-			// if we're still in the same animation frame etc, just use the existing model
-			return cachedModel;
-		}
+		delete cachedModel;
+		cachedModel = NULL;
 	}
 
-	// DG: remember (old)frame and backlerp for the check above if the cached model can be reused
-	lastFrame = frame;
-	lastOldFrame = oldframe;
-	lastBackLerp = backlerp;
-
 	staticModel = new idRenderModelStatic;
 	staticModel->InitEmpty("_MD3_Snapshot_");
 	staticModel->bounds.Clear();