366 lines
11 KiB
JavaScript
366 lines
11 KiB
JavaScript
//
|
|
// largeSphereCollider.js
|
|
//--------------------
|
|
// Provides functions to detect collision against sets of triangles for swept ellipsoids and small rays (low cost, used for green shells).
|
|
// by RHY3756547
|
|
//
|
|
// includes: gl-matrix.js (glMatrix 2.0)
|
|
// /formats/kcl.js
|
|
//
|
|
|
|
window.lsc = new (function() {
|
|
|
|
this.raycast = raycast;
|
|
this.sweepEllipse = sweepEllipse;
|
|
this.pointInTriangle = pointInTriangle; //expose this because its kinda useful
|
|
|
|
var t, colPlane, colPoint, emb, edge, colO, planeNormal;
|
|
|
|
function raycast(pos, dir, scn, error, ignoreList) { //used for shells, bananas and spammable items. Much faster than sphere sweep. Error used to avoid falling through really small seams between tris.
|
|
var error = (error==null)?0:error;
|
|
t=1;
|
|
var tris = getTriList(pos, dir, scn.kcl);
|
|
colPlane = null;
|
|
colPoint = null; //can be calculated from t, but we calculate it anyway so why not include
|
|
colO = null;
|
|
|
|
rayVTris(pos, dir, tris, null, ignoreList, null, error);
|
|
|
|
for (var i=0; i<scn.colEnt.length; i++) {
|
|
var c = scn.colEnt[i];
|
|
var col = c.getCollision();
|
|
|
|
if (vec3.distance(pos, c.pos) < c.colRad) {
|
|
rayVTris(pos, dir, col.tris, col.mat, ignoreList, c, error, col.frame);
|
|
}
|
|
}
|
|
|
|
/*
|
|
for (var i=0; i<tris.length; i++) {
|
|
//first, check if we intersect the plane within reasonable t.
|
|
//only if this happens do we check if the point is in the triangle.
|
|
//we would also only do sphere sweep if this happens.
|
|
|
|
var tri = tris[i];
|
|
|
|
if (ignoreList.indexOf(tri) != -1) continue;
|
|
|
|
var planeConst = -vec3.dot(tri.Normal, tri.Vertices[0]);
|
|
var dist = vec3.dot(tri.Normal, pos) + planeConst;
|
|
var modDir = vec3.dot(tri.Normal, dir);
|
|
if (dist < 0 || modDir == 0) continue; //can't collide with back side of polygons! also can't intersect plane with ray perpendicular to plane
|
|
var newT = -dist/modDir;
|
|
if (newT>0 && newT<t) {
|
|
//we have a winner! check if the plane intersecion point is in the triangle.
|
|
var pt = vec3.add([], pos, vec3.scale([], dir, newT))
|
|
if (pointInTriangle(tri, pt, error)) {
|
|
t = newT;
|
|
colPlane = tri;
|
|
colPoint = pt; //result!
|
|
}
|
|
}
|
|
}
|
|
*/
|
|
|
|
if (colPlane != null) {
|
|
return {
|
|
t: t,
|
|
plane: colPlane,
|
|
colPoint: colPoint,
|
|
object: colO,
|
|
normal: colPlane.Normal
|
|
}
|
|
} else return null;
|
|
}
|
|
|
|
function rayVTris(pos, dir, tris, mat, ignoreList, targ, error, colFrame) {
|
|
for (var i=0; i<tris.length; i++) {
|
|
//first, check if we intersect the plane within reasonable t.
|
|
//only if this happens do we check if the point is in the triangle.
|
|
//we would also only do sphere sweep if this happens.
|
|
var tri = tris[i];
|
|
if (mat != null) {
|
|
if (tri.colFrame === colFrame && tri.cache) {
|
|
tri = tri.cache;
|
|
} else {
|
|
var oT = tri;
|
|
tri = modTri(tris[i], mat);
|
|
oT.cache = tri;
|
|
oT.colFrame = colFrame;
|
|
}
|
|
}
|
|
|
|
if (ignoreList.indexOf(tri) != -1) continue;
|
|
|
|
var planeConst = -vec3.dot(tri.Normal, tri.Vertices[0]);
|
|
var dist = vec3.dot(tri.Normal, pos) + planeConst;
|
|
var modDir = vec3.dot(tri.Normal, dir);
|
|
if (dist < 0 || modDir == 0) continue; //can't collide with back side of polygons! also can't intersect plane with ray perpendicular to plane
|
|
var newT = -dist/modDir;
|
|
if (newT>0 && newT<t) {
|
|
//we have a winner! check if the plane intersecion point is in the triangle.
|
|
var pt = vec3.add([], pos, vec3.scale([], dir, newT))
|
|
if (pointInTriangle(tri, pt, error)) {
|
|
t = newT;
|
|
colPlane = tri;
|
|
colPoint = pt; //result!
|
|
colO = targ;
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
function transformMat3Normal(out, a, m) {
|
|
var x = a[0], y = a[1], z = a[2];
|
|
out[0] = x * m[0] + y * m[4] + z * m[8];
|
|
out[1] = x * m[1] + y * m[5] + z * m[9];
|
|
out[2] = x * m[2] + y * m[6] + z * m[10];
|
|
return out;
|
|
}
|
|
|
|
function modTri(tri, mat) {
|
|
var obj = {};
|
|
obj.Vertices = [];
|
|
obj.Vertices[0] = vec3.transformMat4([], tri.Vertices[0], mat);
|
|
obj.Vertices[1] = vec3.transformMat4([], tri.Vertices[1], mat);
|
|
obj.Vertices[2] = vec3.transformMat4([], tri.Vertices[2], mat);
|
|
|
|
obj.Normal = transformMat3Normal([], tri.Normal, mat);
|
|
vec3.normalize(obj.Normal, obj.Normal);
|
|
obj.CollisionType = tri.CollisionType;
|
|
return obj;
|
|
}
|
|
|
|
function scaleTri(tri, eDim) {
|
|
var obj = {};
|
|
obj.Vertices = [];
|
|
obj.Vertices[0] = vec3.divide([], tri.Vertices[0], eDim);
|
|
obj.Vertices[1] = vec3.divide([], tri.Vertices[1], eDim);
|
|
obj.Vertices[2] = vec3.divide([], tri.Vertices[2], eDim);
|
|
|
|
obj.Normal = tri.Normal
|
|
obj.CollisionType = tri.CollisionType;
|
|
return obj;
|
|
}
|
|
|
|
function sweepEllipse(pos, dir, scn, eDimensions, ignoreList) { //used for karts or things that need to occupy physical space.
|
|
t=1;
|
|
|
|
var ed = vec3.divide([], [1, 1, 1], eDimensions);
|
|
|
|
var tris = getTriList(pos, dir, scn.kcl);
|
|
|
|
var oPos = pos;
|
|
var oDir = dir;
|
|
|
|
var pos = vec3.divide([], pos, eDimensions); //need to rescale position to move into ellipsoid space
|
|
var dir = vec3.divide([], dir, eDimensions);
|
|
|
|
colPlane = null;
|
|
colPoint = null; //can be calculated from t, but we calculate it anyway so why not include
|
|
emb = false;
|
|
edge = false;
|
|
|
|
ellipseVTris(pos, dir, tris, eDimensions, ignoreList, true);
|
|
|
|
for (var i=0; i<scn.colEnt.length; i++) {
|
|
var c = scn.colEnt[i];
|
|
var col = c.getCollision();
|
|
|
|
if (vec3.distance(oPos, c.pos) < c.colRad) {
|
|
ellipseVTris(pos, dir, col.tris, mat4.mul([], mat4.scale([], mat4.create(), ed), col.mat), ignoreList, false, c);
|
|
}
|
|
}
|
|
|
|
if (colPlane != null) {
|
|
var norm = vec3.scale([], dir, t)
|
|
vec3.add(norm, pos, norm);
|
|
vec3.sub(norm, norm, colPoint);
|
|
|
|
if (Math.sqrt(vec3.dot(norm, norm)) < 0.98) emb = true;
|
|
|
|
vec3.mul(colPoint, colPoint, eDimensions);
|
|
|
|
return {
|
|
t: t,
|
|
plane: colPlane,
|
|
colPoint: colPoint,
|
|
normal: norm,
|
|
pNormal: planeNormal,
|
|
embedded: emb,
|
|
object: colO
|
|
}
|
|
} else return null;
|
|
}
|
|
|
|
function ellipseVTris(pos, dir, tris, mat, ignoreList, eDims, targ) {
|
|
for (var i=0; i<tris.length; i++) {
|
|
//first, check if we intersect the plane within reasonable t.
|
|
//only if this happens do we check if the point is in the triangle.
|
|
//we would also only do sphere sweep if this happens.
|
|
|
|
var oTri = tris[i];
|
|
if (ignoreList.indexOf(oTri) != -1) continue;
|
|
|
|
var tri = (eDims)?scaleTri(tris[i], mat):modTri(tris[i], mat);
|
|
var planeConst = -vec3.dot(tri.Normal, tri.Vertices[0]);
|
|
var dist = vec3.dot(tri.Normal, pos) + planeConst;
|
|
var modDir = vec3.dot(tri.Normal, dir);
|
|
|
|
if (dist < 0) continue; //can't collide with back side of polygons! also can't intersect plane with ray perpendicular to plane
|
|
|
|
var t0, t1, embedded = false;
|
|
if (modDir == 0) {
|
|
if (Math.abs(dist) < 1) {
|
|
t0 = 0;
|
|
t1 = 1;
|
|
embedded = true;
|
|
} else {
|
|
t0 = 1000;
|
|
t1 = 2000;
|
|
}
|
|
} else {
|
|
t0 = (1-dist)/modDir;
|
|
t1 = ((-1)-dist)/modDir;
|
|
}
|
|
|
|
if (t0 > t1) { //make sure t0 is smallest value
|
|
var temp = t1;
|
|
t1 = t0;
|
|
t0 = temp;
|
|
}
|
|
|
|
if (!(t0>1 || t1<0)) {
|
|
//we will intersect this triangle's plane within this frame.
|
|
//
|
|
// Three things can happen for the earliest intersection:
|
|
// - sphere intersects plane of triangle (pt on plane projected from new position is inside triangle)
|
|
// - sphere intersects edge of triangle
|
|
// - sphere intersects point of triangle
|
|
|
|
if (t0 < 0) { embedded = true; t0 = 0; }
|
|
if (t1 > 1) t1 = 1;
|
|
|
|
var newT = t0;
|
|
|
|
//sphere intersects plane of triangle
|
|
var pt = [];
|
|
if (embedded) {
|
|
vec3.sub(pt, pos, vec3.scale([], tri.Normal, dist));
|
|
} else {
|
|
vec3.add(pt, pos, vec3.scale([], dir, newT))
|
|
vec3.sub(pt, pt, tri.Normal); //project new position onto plane along normal
|
|
}
|
|
if (pointInTriangle(tri, pt, 0) && newT<t) {
|
|
t = newT;
|
|
colPlane = oTri;
|
|
colPoint = pt; //result!
|
|
colO = targ;
|
|
edge = false;
|
|
emb = embedded;
|
|
planeNormal = tri.Normal;
|
|
continue;
|
|
}
|
|
|
|
//no inside intersection check vertices:
|
|
for (var j=0; j<=2; j++) {
|
|
var vert = vec3.sub([], pos, tri.Vertices[j]);
|
|
var root = getSmallestRoot(vec3.dot(dir, dir), 2*vec3.dot(dir, vert), vec3.dot(vert, vert)-1, t);
|
|
if (root != null) {
|
|
t = root;
|
|
colPlane = oTri;
|
|
colO = targ;
|
|
colPoint = vec3.clone(tri.Vertices[j]); //result!
|
|
planeNormal = tri.Normal;
|
|
edge = false;
|
|
}
|
|
}
|
|
|
|
//... and lines
|
|
|
|
for (var j=0; j<=2; j++) {
|
|
var vert = tri.Vertices[j];
|
|
var nextV = tri.Vertices[(j+1)%3];
|
|
|
|
var distVert = vec3.sub([], vert, pos);
|
|
var distLine = vec3.sub([], nextV, vert);
|
|
|
|
var edgeDist = vec3.dot(distLine, distLine);
|
|
var edgeDotVelocity = vec3.dot(distLine, dir);
|
|
var edgeDotVert = vec3.dot(distVert, distLine);
|
|
|
|
var root = getSmallestRoot(
|
|
edgeDist*(-1)*vec3.dot(dir, dir) + edgeDotVelocity*edgeDotVelocity,
|
|
edgeDist*2*vec3.dot(dir, distVert) - 2*edgeDotVelocity*edgeDotVert,
|
|
edgeDist*(1-vec3.dot(distVert, distVert)) + edgeDotVert*edgeDotVert,
|
|
t
|
|
);
|
|
|
|
if (root != null) {
|
|
var edgePos = (edgeDotVelocity*root - edgeDotVert)/edgeDist;
|
|
|
|
if (edgePos >= 0 && edgePos <= 1) {
|
|
t = root;
|
|
colPlane = oTri;
|
|
colO = targ;
|
|
colPoint = vec3.add([], vert, vec3.scale(distLine, distLine, edgePos)); //result!
|
|
planeNormal = tri.Normal;
|
|
edge = true;
|
|
}
|
|
}
|
|
}
|
|
|
|
}
|
|
}
|
|
}
|
|
|
|
function getSmallestRoot(a, b, c, upperLimit) {
|
|
var det = (b*b) - 4*(a*c);
|
|
if (det<0) return null; //no result :'(
|
|
else {
|
|
det = Math.sqrt(det);
|
|
var root1 = ((-b)-det)/(2*a)
|
|
var root2 = ((-b)+det)/(2*a)
|
|
|
|
if (root1 > root2) { //ensure root1 is smallest
|
|
var temp = root1;
|
|
root1 = root2;
|
|
root2 = temp;
|
|
}
|
|
|
|
if (root1>0 && root1<upperLimit) {
|
|
return root1;
|
|
} else if (root2>0 && root2<upperLimit) {
|
|
return root2;
|
|
} else {
|
|
return null;
|
|
}
|
|
}
|
|
}
|
|
|
|
function pointInTriangle(tri, point, error) { //barycentric check
|
|
//compute direction vectors to the other verts and the point
|
|
var v0 = vec3.sub([], tri.Vertices[2], tri.Vertices[0]);
|
|
var v1 = vec3.sub([], tri.Vertices[1], tri.Vertices[0]);
|
|
var v2 = vec3.sub([], point, tri.Vertices[0]);
|
|
|
|
//we need to find u and v across the two vectors v0 and v1 such that adding them will result in our point's position
|
|
//where the unit length of both vectors v0 and v1 is 1, the sum of both u and v should not exceed 1 and neither should be negative
|
|
|
|
var dot00 = vec3.dot(v0, v0); var dot01 = vec3.dot(v0, v1); var dot02 = vec3.dot(v0, v2);
|
|
var dot11 = vec3.dot(v1, v1); var dot12 = vec3.dot(v1, v2);
|
|
//dot11 and dot00 result in the square of the distance for v0 and v1
|
|
|
|
var inverse = 1/(dot00*dot11 - dot01*dot01);
|
|
var u = (dot11*dot02 - dot01*dot12)*inverse;
|
|
var v = (dot00*dot12 - dot01*dot02)*inverse;
|
|
|
|
return (u>=-error && v>=-error && (u+v)<1+error);
|
|
}
|
|
|
|
function getTriList(pos, diff, kclO) { //gets tris from kcl around a line. currently only fetches from middle point of line, but should include multiple samples for large differences in future.
|
|
var sample = vec3.add([], pos, vec3.scale([], diff, 0.5))
|
|
return kclO.getPlanesAt(sample[0], sample[1], sample[2]);
|
|
}
|
|
|
|
})(); |