split apart modules

collision.cm

@@ -0,0 +1,235 @@
+// Collision module for lance3d
+
+// Private collider storage
+var _colliders = []
+var _collider_id = 0
+
+function clear() {
+  _colliders = []
+}
+
+function add_sphere(transform, radius, opts) {
+  opts = opts || {}
+  var c = {
+    id: _collider_id++,
+    type: "sphere",
+    transform: transform,
+    radius: radius,
+    layer_mask: opts.layer_mask || 1,
+    user: opts.user
+  }
+  _colliders.push(c)
+  return c
+}
+
+function add_box(transform, sx, sy, sz, opts) {
+  opts = opts || {}
+  var c = {
+    id: _collider_id++,
+    type: "box",
+    transform: transform,
+    sx: sx, sy: sy, sz: sz,
+    layer_mask: opts.layer_mask || 1,
+    user: opts.user
+  }
+  _colliders.push(c)
+  return c
+}
+
+function remove(collider) {
+  for (var i = 0; i < _colliders.length; i++) {
+    if (_colliders[i].id == collider.id) {
+      _colliders.splice(i, 1)
+      return true
+    }
+  }
+  return false
+}
+
+function overlaps(layer_mask_a, layer_mask_b) {
+  var results = []
+  for (var i = 0; i < _colliders.length; i++) {
+    for (var j = i + 1; j < _colliders.length; j++) {
+      var a = _colliders[i]
+      var b = _colliders[j]
+      
+      if (layer_mask_a != null && !(a.layer_mask & layer_mask_a)) continue
+      if (layer_mask_b != null && !(b.layer_mask & layer_mask_b)) continue
+      
+      if (_check_collision(a, b)) {
+        results.push({a: a, b: b})
+      }
+    }
+  }
+  return results
+}
+
+function raycast(ox, oy, oz, dx, dy, dz, opts) {
+  opts = opts || {}
+  var max_dist = opts.max_dist || 1000000
+  var layer_mask = opts.layer_mask || 0xFFFFFFFF
+  
+  // Normalize direction
+  var len = Math.sqrt(dx*dx + dy*dy + dz*dz)
+  if (len < 0.0001) return null
+  dx /= len
+  dy /= len
+  dz /= len
+  
+  var closest = null
+  var closest_dist = max_dist
+  
+  for (var i = 0; i < _colliders.length; i++) {
+    var c = _colliders[i]
+    if (!(c.layer_mask & layer_mask)) continue
+    
+    var hit = null
+    if (c.type == "sphere") {
+      hit = _ray_sphere(ox, oy, oz, dx, dy, dz, c)
+    } else if (c.type == "box") {
+      hit = _ray_box(ox, oy, oz, dx, dy, dz, c)
+    }
+    
+    if (hit && hit.distance < closest_dist) {
+      closest = hit
+      closest_dist = hit.distance
+    }
+  }
+  
+  return closest
+}
+
+function _get_position(transform) {
+  if (!transform) return {x: 0, y: 0, z: 0}
+  // If transform is a matrix (array of 16), extract translation
+  if (transform.length == 16) {
+    return {x: transform[12], y: transform[13], z: transform[14]}
+  }
+  // If transform is an object with x,y,z
+  if (transform.x != null) {
+    return {x: transform.x, y: transform.y, z: transform.z}
+  }
+  return {x: 0, y: 0, z: 0}
+}
+
+function _check_collision(a, b) {
+  var pa = _get_position(a.transform)
+  var pb = _get_position(b.transform)
+  
+  var dx = pb.x - pa.x
+  var dy = pb.y - pa.y
+  var dz = pb.z - pa.z
+  var dist = Math.sqrt(dx*dx + dy*dy + dz*dz)
+  
+  // Simple sphere-sphere approximation
+  var ra = a.radius || Math.max(a.sx || 0, a.sy || 0, a.sz || 0)
+  var rb = b.radius || Math.max(b.sx || 0, b.sy || 0, b.sz || 0)
+  return dist < ra + rb
+}
+
+function _ray_sphere(ox, oy, oz, dx, dy, dz, sphere) {
+  var pos = _get_position(sphere.transform)
+  var r = sphere.radius
+  
+  // Vector from ray origin to sphere center
+  var lx = pos.x - ox
+  var ly = pos.y - oy
+  var lz = pos.z - oz
+  
+  // Project onto ray direction
+  var tca = lx*dx + ly*dy + lz*dz
+  if (tca < 0) return null
+  
+  var d2 = lx*lx + ly*ly + lz*lz - tca*tca
+  var r2 = r*r
+  if (d2 > r2) return null
+  
+  var thc = Math.sqrt(r2 - d2)
+  var t = tca - thc
+  if (t < 0) t = tca + thc
+  if (t < 0) return null
+  
+  var hx = ox + dx*t
+  var hy = oy + dy*t
+  var hz = oz + dz*t
+  
+  // Normal at hit point
+  var nx = (hx - pos.x) / r
+  var ny = (hy - pos.y) / r
+  var nz = (hz - pos.z) / r
+  
+  return {
+    x: hx, y: hy, z: hz,
+    nx: nx, ny: ny, nz: nz,
+    distance: t,
+    collider: sphere
+  }
+}
+
+function _ray_box(ox, oy, oz, dx, dy, dz, box) {
+  var pos = _get_position(box.transform)
+  var hx = (box.sx || 1) / 2
+  var hy = (box.sy || 1) / 2
+  var hz = (box.sz || 1) / 2
+  
+  var minx = pos.x - hx, maxx = pos.x + hx
+  var miny = pos.y - hy, maxy = pos.y + hy
+  var minz = pos.z - hz, maxz = pos.z + hz
+  
+  var tmin = -1000000, tmax = 1000000
+  var nx = 0, ny = 0, nz = 0
+  
+  // X slab
+  if (Math.abs(dx) > 0.0001) {
+    var t1 = (minx - ox) / dx
+    var t2 = (maxx - ox) / dx
+    if (t1 > t2) { var tmp = t1; t1 = t2; t2 = tmp }
+    if (t1 > tmin) { tmin = t1; nx = dx > 0 ? -1 : 1; ny = 0; nz = 0 }
+    if (t2 < tmax) tmax = t2
+  } else if (ox < minx || ox > maxx) {
+    return null
+  }
+  
+  // Y slab
+  if (Math.abs(dy) > 0.0001) {
+    var t1 = (miny - oy) / dy
+    var t2 = (maxy - oy) / dy
+    if (t1 > t2) { var tmp = t1; t1 = t2; t2 = tmp }
+    if (t1 > tmin) { tmin = t1; nx = 0; ny = dy > 0 ? -1 : 1; nz = 0 }
+    if (t2 < tmax) tmax = t2
+  } else if (oy < miny || oy > maxy) {
+    return null
+  }
+  
+  // Z slab
+  if (Math.abs(dz) > 0.0001) {
+    var t1 = (minz - oz) / dz
+    var t2 = (maxz - oz) / dz
+    if (t1 > t2) { var tmp = t1; t1 = t2; t2 = tmp }
+    if (t1 > tmin) { tmin = t1; nx = 0; ny = 0; nz = dz > 0 ? -1 : 1 }
+    if (t2 < tmax) tmax = t2
+  } else if (oz < minz || oz > maxz) {
+    return null
+  }
+  
+  if (tmin > tmax || tmax < 0) return null
+  
+  var t = tmin > 0 ? tmin : tmax
+  if (t < 0) return null
+  
+  return {
+    x: ox + dx*t, y: oy + dy*t, z: oz + dz*t,
+    nx: nx, ny: ny, nz: nz,
+    distance: t,
+    collider: box
+  }
+}
+
+return {
+  clear: clear,
+  add_sphere: add_sphere,
+  add_box: add_box,
+  remove: remove,
+  overlaps: overlaps,
+  raycast: raycast
+}