SuperHQ Motion experiment: locomotion and action checkpoints, runtime, clips, evaluation
6adbbb1 verified | const clamp=(v,a,b)=>Math.max(a,Math.min(b,v)); | |
| const lerp=(a,b,u)=>a+(b-a)*u; | |
| export function slerp(a,b,u) { | |
| let dot=a.reduce((s,v,i)=>s+v*b[i],0); | |
| if(dot<0){b=b.map(v=>-v);dot=-dot;} | |
| dot=clamp(dot,-1,1); | |
| const angle=Math.acos(dot),s=Math.sin(angle); | |
| const q=dot>.9995?a.map((v,i)=>lerp(v,b[i],u)): | |
| a.map((v,i)=>(Math.sin((1-u)*angle)*v+Math.sin(u*angle)*b[i])/s); | |
| const length=Math.hypot(...q);return q.map(v=>v/length); | |
| } | |
| export function blendPoses(a,b,u) { | |
| return {rootPosition:a.rootPosition.map((v,i)=>lerp(v,b.rootPosition[i],u)), | |
| localQuaternions:a.localQuaternions.map((q,i)=>slerp(q,b.localQuaternions[i],u)), | |
| contacts:a.contacts.map((v,i)=>lerp(v,b.contacts[i],u))}; | |
| } | |
| /** Forward kinematics, shared by the raw experiment and its metrics. */ | |
| export function worldPositions(pose,rig) { | |
| const mul=(a,b)=>[ | |
| a[3]*b[0]+a[0]*b[3]+a[1]*b[2]-a[2]*b[1], | |
| a[3]*b[1]-a[0]*b[2]+a[1]*b[3]+a[2]*b[0], | |
| a[3]*b[2]+a[0]*b[1]-a[1]*b[0]+a[2]*b[3], | |
| a[3]*b[3]-a[0]*b[0]-a[1]*b[1]-a[2]*b[2]]; | |
| const rotate=(v,q)=>mul(mul(q,[...v,0]),[-q[0],-q[1],-q[2],q[3]]).slice(0,3); | |
| const positions=[],rotations=[]; | |
| for(let i=0;i<rig.names.length;i++) { | |
| const parent=rig.parents[i],q=pose.localQuaternions[i]; | |
| if(parent<0){positions.push(pose.rootPosition.slice());rotations.push(q);} | |
| else{const o=rotate(rig.offsets[i],rotations[parent]);positions.push(o.map((v,j)=>v+positions[parent][j]));rotations.push(mul(rotations[parent],q));} | |
| } | |
| return positions; | |
| } | |
| /** The game checkpoints' canonical Head frame was derived from the neck-to-head | |
| * vector during source conversion, so a level source head appears pitched | |
| * 10.9 degrees forward (measured on the Quaternius A_TPose; see | |
| * docs/motion-one-shot-actions-and-character.md). Correct it before display. | |
| * Locomotion, actions and clips share the bias; poses are otherwise unchanged. | |
| */ | |
| export const HEAD_PITCH_BIAS_DEGREES=10.9; | |
| export function correctHeadPitch(pose,degrees=HEAD_PITCH_BIAS_DEGREES) { | |
| const h=-degrees*Math.PI/360,r=[Math.sin(h),0,0,Math.cos(h)],q=pose.localQuaternions[6]; | |
| const head=[q[3]*r[0]+q[0]*r[3]+q[1]*r[2]-q[2]*r[1],q[3]*r[1]-q[0]*r[2]+q[1]*r[3]+q[2]*r[0], | |
| q[3]*r[2]+q[0]*r[1]-q[1]*r[0]+q[2]*r[3],q[3]*r[3]-q[0]*r[0]-q[1]*r[1]-q[2]*r[2]]; | |
| const localQuaternions=pose.localQuaternions.slice();localQuaternions[6]=head; | |
| return {...pose,localQuaternions}; | |
| } | |