//----------------------------------------------
// U P D A T E M O D E L A N I M A T I O N S
//----------------------------------------------
///<summary> Gets the animation frame (based on elapsed time) for all nodes and loads them into the model node transforms. </summary>
private void UpdateModelAnimations(GameTime gameTime)
{
if (animations.Count <= 0 || currentAnim >= animations.Count)
{
return;
}
AnimationTimeLogic(gameTime); // process what to do based on animation time (frames, duration, complete | looping)
int cnt = animations[currentAnim].animatedNodes.Count; // loop thru animated nodes
for (int n = 0; n < cnt; n++)
{
AnimNodes animNode = animations[currentAnim].animatedNodes[n]; // get animation keyframe lists (each animNode)
ModelNode node = animNode.nodeRef; // get bone associated with this animNode (could be mesh-node)
node.local_mtx = animations[currentAnim].Interpolate(currentAnimFrameTime, animNode); // interpolate keyframes (animate local matrix) for this bone
}
}
public List <AnimNodes> animatedNodes; // holds the animated nodes
// I N T E R P O L A T E
///<summary> animation blending between key-frames </summary>
public Matrix Interpolate(double animTime, AnimNodes nodeAnim)
{
var durationSecs = DurationInSeconds + DurationInSecondsAdded;
while (animTime > durationSecs) // If the requested play-time is past the end of the animation, loop it (ie: time = 20 but duration = 16 so time becomes 4)
{
animTime -= durationSecs;
}
Quaternion q1 = nodeAnim.qrot[0], q2 = q1; // init rot as entry 0 for both keys (init may be needed cuz conditional value assignment can upset compiler)
Vector3 p1 = nodeAnim.position[0], p2 = p1; // " pos
Vector3 s1 = nodeAnim.scale[0], s2 = s1; // " scale
double tq1 = nodeAnim.qrotTime[0], tq2 = tq1; // " rot-time
double tp1 = nodeAnim.positionTime[0], tp2 = tp1; // " pos-time
double ts1 = nodeAnim.scaleTime[0], ts2 = ts1; // " scale-time
// GET ROTATION KEYFRAMES
int end_t_index = nodeAnim.qrotTime.Count - 1; // final time's index (starting with qrot cuz we do it first - we'll cahnge this variable for pos and scale)
int end_index = nodeAnim.qrot.Count - 1; // final rot frame
var end_time = nodeAnim.qrotTime[end_t_index]; // get final rotation-time
if (animTime > end_time)
{ // if animTime is past final rotation-time: Set to interpolate between last and first frames (for animation-loop)
tq1 = end_time; // key 1 time is last keyframe and time 2 is time taken after to get to frame 0 (see below)
tq2 += durationSecs; // total duration accounting for time to loop from last frame to frame 0 (with DurationInSecondsAdded)
q1 = nodeAnim.qrot[end_index]; // get final quaternion (count-1), NOTE: q2 already set above (key frame 0)
}
else
{
int frame2 = end_index, frame1; // animTime t = frame2
for (; frame2 > -1; frame2--) // loop from last index to 0 (until find correct place on timeline):
{
var t = nodeAnim.qrotTime[frame2]; // what's the time at this frame?
if (t < animTime)
{
break; // if the current_time > the frame time then we've found the spot we're looking for (break out)
}
}
if (frame2 < end_index)
{
frame2++; // at this point the frame2 is 1 less than what we're looking for so add 1
}
q2 = nodeAnim.qrot[frame2];
tq2 = nodeAnim.qrotTime[frame2];
frame1 = frame2 - 1;
if (frame1 < 0)
{
frame1 = end_index; // loop frame1 to last frame
tq1 = nodeAnim.qrotTime[frame1] - durationSecs; // Using: frame2time - frame1time, so we need time1 to be less _ thus: subtract durationSecs to fix it
}
else
{
tq1 = nodeAnim.qrotTime[frame1]; // get time1
}
q1 = nodeAnim.qrot[frame1];
}
// GET POSITION KEY FRAMES
end_t_index = nodeAnim.positionTime.Count - 1; // final time's index
end_index = nodeAnim.position.Count - 1; // final pos frame
end_time = nodeAnim.positionTime[end_t_index]; // get final position-time
if (animTime > end_time) // if animTime is past final pos-time: Set to interpolate between last and first frames (for animation-loop)
{
tp1 = end_time; // key 1 time is last keyframe and time 2 is time taken after to get to frame 0 (see below)
tp2 += durationSecs; // total duration accounting for time to loop from last frame to frame 0 (with DurationInSecondsAdded)
p1 = nodeAnim.position[end_index]; // get final position (count-1), NOTE: q2 already set above (key frame 0)
}
else
{
int frame2 = end_index, frame1;
for (; frame2 > -1; frame2--) // loop from last index to 0 (until find correct place on timeline):
{
var t = nodeAnim.positionTime[frame2]; // what's the time at this frame?
if (t < animTime)
{
break; // if the current_time > the frame time then we've found the spot we're looking for (break out)
}
}
if (frame2 < end_index)
{
frame2++; // at this point the frame2 is 1 less than what we're looking for so add 1
}
p2 = nodeAnim.position[frame2];
tp2 = nodeAnim.positionTime[frame2];
frame1 = frame2 - 1;
if (frame1 < 0)
{
frame1 = end_index; // loop frame1 to last frame
tp1 = nodeAnim.positionTime[frame1] - durationSecs; // Using: frame2time - frame1time, so we need time1 to be less _ thus: subtract durationSecs to fix it
}
else
{
tp1 = nodeAnim.positionTime[frame1]; // get time1
}
p1 = nodeAnim.position[frame1];
}
// GET SCALE KEYFRAMES
end_t_index = nodeAnim.scaleTime.Count - 1; // final time's index
end_index = nodeAnim.scale.Count - 1; // final scale frame
end_time = nodeAnim.scaleTime[end_t_index]; // get final scale-time
if (animTime > end_time) // if animTime is past final scale-time: Set to interpolate between last and first frames (for animation-loop)
{
ts1 = end_time; // key 1 time is last keyframe and time 2 is time taken after to get to frame 0 (see below)
ts2 += durationSecs; // total duration accounting for time to loop from last frame to frame 0 (with DurationInSecondsAdded)
s1 = nodeAnim.scale[end_index]; // get final scale (count-1), NOTE: q2 already set above (key frame 0)
}
else
{
int frame2 = end_index, frame1;
for (; frame2 > -1; frame2--) // loop from last index to 0 (until find correct place on timeline):
{
var t = nodeAnim.scaleTime[frame2]; // what's the time at this frame?
if (animTime > t)
{
break; // if the current_time > the frame time then we've found the spot we're looking for (break out)
}
}
if (frame2 < end_index)
{
frame2++; // at this point the frame2 is 1 less than what we're looking for so add 1
}
s2 = nodeAnim.scale[frame2];
ts2 = nodeAnim.scaleTime[frame2];
frame1 = frame2 - 1;
if (frame1 < 0)
{
frame1 = end_index; // loop frame1 to last frame
ts1 = nodeAnim.scaleTime[frame1] - durationSecs; // Using: frame2time - frame1time, so we need time1 to be less _ thus: subtract durationSecs to fix it
}
else
{
ts1 = nodeAnim.scaleTime[frame1]; // get time1
}
s1 = nodeAnim.scale[frame1];
}
float tqi = 0, tpi = 0, tsi = 0;
Quaternion q;
tqi = (float)GetInterpolateTimePercent(tq1, tq2, animTime); // get the time% (0-1)
q = Quaternion.Slerp(q1, q2, tqi); // blend the rotation between keys using the time percent
Vector3 p;
tpi = (float)GetInterpolateTimePercent(tp1, tp2, animTime); // "
p = Vector3.Lerp(p1, p2, tpi);
Vector3 s;
tsi = (float)GetInterpolateTimePercent(ts1, ts2, animTime); // "
s = Vector3.Lerp(s1, s2, tsi);
var ms = Matrix.CreateScale(s);
var mr = Matrix.CreateFromQuaternion(q);
var mt = Matrix.CreateTranslation(p);
var m = ms * mr * mt; // S,R,T
return(m);
} // Interpolate
