void EMIHead::lookAt(bool entering, const Math::Vector3d &point, float rate, const Math::Matrix4 &matrix) {
if (!_cost->_emiSkel || !_cost->_emiSkel->_obj)
return;
if (_jointName.empty())
return;
Joint *joint = _cost->_emiSkel->_obj->getJointNamed(_jointName);
if (!joint)
return;
Math::Quaternion lookAtQuat; // Note: Identity if not looking at anything.
if (entering) {
Math::Matrix4 jointToWorld = _cost->getOwner()->getFinalMatrix() * joint->_finalMatrix;
Math::Vector3d jointWorldPos = jointToWorld.getPosition();
Math::Matrix4 worldToJoint = jointToWorld;
worldToJoint.invertAffineOrthonormal();
Math::Vector3d targetDir = (point + _offset) - jointWorldPos;
targetDir.normalize();
const Math::Vector3d worldUp(0, 1, 0);
Math::Vector3d frontDir = Math::Vector3d(worldToJoint(0, 1), worldToJoint(1, 1), worldToJoint(2, 1)); // Look straight ahead. (+Y)
Math::Vector3d modelFront(0, 0, 1);
Math::Vector3d modelUp(0, 1, 0);
joint->_absMatrix.inverseRotate(&modelFront);
joint->_absMatrix.inverseRotate(&modelUp);
// Generate a world-space look at matrix.
Math::Matrix4 lookAtTM;
lookAtTM.setToIdentity();
if (Math::Vector3d::dotProduct(targetDir, worldUp) >= 0.98f) // Avoid singularity if trying to look straight up.
lookAtTM.buildFromTargetDir(modelFront, targetDir, modelUp, -frontDir); // Instead of orienting head towards scene up, orient head towards character "back",
else if (Math::Vector3d::dotProduct(targetDir, worldUp) <= -0.98f) // Avoid singularity if trying to look straight down.
lookAtTM.buildFromTargetDir(modelFront, targetDir, modelUp, frontDir); // Instead of orienting head towards scene down, orient head towards character "front",
else
lookAtTM.buildFromTargetDir(modelFront, targetDir, modelUp, worldUp);
// Convert from world-space to joint-space.
lookAtTM = worldToJoint * lookAtTM;
// Apply angle limits.
Math::Angle p, y, r;
lookAtTM.getXYZ(&y, &p, &r, Math::EO_ZXY);
y.clampDegrees(_yawRange);
p.clampDegrees(_minPitch, _maxPitch);
r.clampDegrees(30.0f);
lookAtTM.buildFromXYZ(y, p, r, Math::EO_ZXY);
lookAtQuat.fromMatrix(lookAtTM.getRotation());
}
if (_headRot != lookAtQuat) {
Math::Quaternion diff = _headRot.inverse() * lookAtQuat;
float angle = 2 * acos(diff.w());
if (diff.w() < 0.0f) {
angle = 2 * (float)M_PI - angle;
}
float turnAmount = g_grim->getPerSecond(rate * ((float)M_PI / 180.0f));
if (turnAmount < angle)
_headRot = _headRot.slerpQuat(lookAtQuat, turnAmount / angle);
else
_headRot = lookAtQuat;
}
if (_headRot != Math::Quaternion()) { // If not identity..
joint->_animMatrix = joint->_animMatrix * _headRot.toMatrix();
joint->_animQuat = joint->_animQuat * _headRot;
_cost->_emiSkel->_obj->commitAnim();
}
}
void Head::Joint::orientTowards(bool entering, const Math::Vector3d &point, float rate, const Math::Matrix4 &matrix,
float maxPitch, float maxYaw, float maxRoll, float constrain) {
float step = g_grim->getPerSecond(rate);
float yawStep = step;
float pitchStep = step / 3.0f;
float rollStep = step / 3.0f;
if (!_node)
return;
// Make sure we have up-to-date world transform matrices computed for the joint nodes of this character.
_node->_needsUpdate = true;
ModelNode *p = _node;
while (p->_parent) {
p = p->_parent;
p->_needsUpdate = true;
}
p->setMatrix(matrix);
p->update();
Math::Vector3d modelFront; // the modeling convention for the forward direction.
Math::Vector3d modelUp; // the modeling convention for the upward direction.
Math::Vector3d frontDir; // Character front facing direction vector in world space (global scene coordinate space)
// the character head coordinate frame is: +Y forward, +Z up, +X right.
frontDir = Math::Vector3d(_node->_matrix(0,1), _node->_matrix(1,1), _node->_matrix(2,1)); // Look straight ahead. (+Y)
modelFront = Math::Vector3d(0,1,0);
modelUp = Math::Vector3d(0,0,1);
// v is the world space direction vector this character should be looking towards.
Math::Vector3d targetDir = point - _node->_pivotMatrix.getPosition();
if (!entering)
targetDir = frontDir;
if (targetDir.isZero())
return;
targetDir.normalize();
// The vector v is in world space, so generate the world space lookat matrix for the desired head facing
// orientation.
Math::Matrix4 lookAtTM;
lookAtTM.setToIdentity();
const Math::Vector3d worldUp(0,0,1); // The Residual scene convention: +Z is world space up.
if (Math::Vector3d::dotProduct(targetDir, worldUp) >= 0.98f) // Avoid singularity if trying to look straight up.
lookAtTM.buildFromTargetDir(modelFront, targetDir, modelUp, -frontDir); // Instead of orienting head towards scene up, orient head towards character "back",
// i.e. when you look straight up, your head up vector tilts/arches to point straight backwards.
else if (Math::Vector3d::dotProduct(targetDir, worldUp) <= -0.98f) // Avoid singularity if trying to look straight down.
lookAtTM.buildFromTargetDir(modelFront, targetDir, modelUp, frontDir); // Instead of orienting head towards scene down, orient head towards character "front",
// i.e. when you look straight down, your head up vector tilts/arches to point straight forwards.
else
lookAtTM.buildFromTargetDir(modelFront, targetDir, modelUp, worldUp);
// The above specifies the world space orientation of this bone, but we need to output
// the orientation in parent space (as yaw/pitch/roll).
// Get the coordinate frame in which we need to produce the character head yaw/pitch/roll values.
Math::Matrix4 parentWorldTM;
if (_node->_parent)
parentWorldTM = _node->_parent->_matrix;
// While we could compute the desired lookat direction directly in the above coordinate frame,
// it is preferrable to compute the lookat direction with respect to the head orientation in
// the keyframe animation. This is because the LUA scripts specify the maximum head yaw, pitch and
// roll values with respect to those keyframe animations. If the lookat was simply computed
// directly in the space of the parent, we couldn't apply the head maxYaw/Pitch/Roll constraints
// properly. So, compute the coordinate frame of this bone in the keyframe animation.
Math::Matrix4 animFrame = _node->_localMatrix;
parentWorldTM = parentWorldTM * animFrame;
parentWorldTM.invertAffineOrthonormal();
// Convert lookAtTM orientation from world space to parent-with-keyframe-animation space.
lookAtTM = parentWorldTM * lookAtTM;
// Decompose to yaw-pitch-roll (+Z, +X, +Y).
// In this space, Yaw is +Z. Pitch is +X. Roll is +Y.
Math::Angle y, pt, r;
lookAtTM.getPitchYawRoll(&pt, &y, &r);
y = y * constrain;
pt = pt * constrain;
r = r * constrain;
// Constrain the maximum head movement, as desired by the game LUA scripts.
y.clampDegrees(maxYaw);
pt.clampDegrees(maxPitch);
r.clampDegrees(maxRoll);
// Also limit yaw, pitch and roll to make at most a movement as large as the given max step size during this frame.
// This will produce a slow head-turning animation instead of immediately snapping to the
// target lookat orientation.
if (y - _yaw > yawStep)
y = _yaw + yawStep;
if (_yaw - y > yawStep)
y = _yaw - yawStep;
if (pt - _pitch > pitchStep)
pt = _pitch + pitchStep;
if (_pitch - pt > pitchStep)
pt = _pitch - pitchStep;
if (r - _roll > rollStep)
r = _roll + rollStep;
if (_roll - r > rollStep)
r = _roll - rollStep;
// Remember how far we animated the head this frame, and we'll continue from here the next frame.
_pitch = pt;
_yaw = y;
_roll = r;
// Assemble ypr back to a matrix.
// This matrix is the head orientation with respect to parent-with-keyframe-animation space.
lookAtTM.buildFromPitchYawRoll(pt, y, r);
// What follows is a hack: Since translateObject(ModelNode *node, bool reset) in this file,
// and GfxOpenGL/GfxTinyGL::drawHierachyNode concatenate transforms incorrectly, by summing up
// euler angles, do a hack here where we do the proper transform here already, and *subtract off*
// the YPR scalars from the animYPR scalars to cancel out the values that those pieces of code
// will later accumulate. After those pieces of code have been fixed, the following lines can
// be deleted, and this function can simply output the contents of pt, y and r variables above.
lookAtTM = animFrame * lookAtTM;
lookAtTM.getPitchYawRoll(&pt, &y, &r);
_node->_animYaw = y - _node->_yaw;
_node->_animPitch = pt - _node->_pitch;
_node->_animRoll = r - _node->_roll;
}