mirror of
https://github.com/HifiExperiments/overte.git
synced 2025-06-20 14:29:09 +02:00
377 lines
15 KiB
C++
377 lines
15 KiB
C++
//
|
|
// AABox.cpp
|
|
// libraries/octree/src
|
|
//
|
|
// Created by Brad Hefta-Gaub on 04/11/13.
|
|
// Copyright 2013 High Fidelity, Inc.
|
|
//
|
|
// Distributed under the Apache License, Version 2.0.
|
|
// See the accompanying file LICENSE or http://www.apache.org/licenses/LICENSE-2.0.html
|
|
//
|
|
|
|
#include "SharedUtil.h"
|
|
|
|
#include "AABox.h"
|
|
#include "GeometryUtil.h"
|
|
|
|
AABox::AABox(const glm::vec3& corner, float size) :
|
|
_corner(corner), _scale(size) {
|
|
};
|
|
|
|
AABox::AABox() : _corner(0,0,0), _scale(0) {
|
|
};
|
|
|
|
glm::vec3 AABox::calcCenter() const {
|
|
glm::vec3 center(_corner);
|
|
center += (glm::vec3(_scale, _scale, _scale) * 0.5f);
|
|
return center;
|
|
}
|
|
|
|
glm::vec3 AABox::calcTopFarLeft() const {
|
|
glm::vec3 topFarLeft(_corner);
|
|
topFarLeft += glm::vec3(_scale, _scale, _scale);
|
|
return topFarLeft;
|
|
};
|
|
|
|
void AABox::scale(float scale) {
|
|
_corner = _corner * scale;
|
|
_scale = _scale * scale;
|
|
}
|
|
|
|
glm::vec3 AABox::getVertex(BoxVertex vertex) const {
|
|
switch (vertex) {
|
|
case BOTTOM_LEFT_NEAR:
|
|
return _corner + glm::vec3(_scale, 0, 0);
|
|
case BOTTOM_RIGHT_NEAR:
|
|
return _corner;
|
|
case TOP_RIGHT_NEAR:
|
|
return _corner + glm::vec3(0, _scale, 0);
|
|
case TOP_LEFT_NEAR:
|
|
return _corner + glm::vec3(_scale, _scale, 0);
|
|
case BOTTOM_LEFT_FAR:
|
|
return _corner + glm::vec3(_scale, 0, _scale);
|
|
case BOTTOM_RIGHT_FAR:
|
|
return _corner + glm::vec3(0, 0, _scale);
|
|
case TOP_RIGHT_FAR:
|
|
return _corner + glm::vec3(0, _scale, _scale);
|
|
default: //quiet windows warnings
|
|
case TOP_LEFT_FAR:
|
|
return _corner + glm::vec3(_scale, _scale, _scale);
|
|
}
|
|
}
|
|
|
|
void AABox::setBox(const glm::vec3& corner, float scale) {
|
|
_corner = corner;
|
|
_scale = scale;
|
|
}
|
|
|
|
glm::vec3 AABox::getVertexP(const glm::vec3& normal) const {
|
|
glm::vec3 result = _corner;
|
|
if (normal.x > 0) {
|
|
result.x += _scale;
|
|
}
|
|
if (normal.y > 0) {
|
|
result.y += _scale;
|
|
}
|
|
if (normal.z > 0) {
|
|
result.z += _scale;
|
|
}
|
|
return result;
|
|
}
|
|
|
|
glm::vec3 AABox::getVertexN(const glm::vec3& normal) const {
|
|
glm::vec3 result = _corner;
|
|
|
|
if (normal.x < 0) {
|
|
result.x += _scale;
|
|
}
|
|
|
|
if (normal.y < 0) {
|
|
result.y += _scale;
|
|
}
|
|
|
|
if (normal.z < 0) {
|
|
result.z += _scale;
|
|
}
|
|
|
|
return result;
|
|
}
|
|
|
|
// determines whether a value is within the extents
|
|
static bool isWithin(float value, float corner, float size) {
|
|
return value >= corner && value <= corner + size;
|
|
}
|
|
|
|
bool AABox::contains(const glm::vec3& point) const {
|
|
return isWithin(point.x, _corner.x, _scale) &&
|
|
isWithin(point.y, _corner.y, _scale) &&
|
|
isWithin(point.z, _corner.z, _scale);
|
|
}
|
|
|
|
bool AABox::contains(const AABox& otherBox) const {
|
|
for (int v = BOTTOM_LEFT_NEAR; v < TOP_LEFT_FAR; v++) {
|
|
glm::vec3 vertex = otherBox.getVertex((BoxVertex)v);
|
|
if (!contains(vertex)) {
|
|
return false;
|
|
}
|
|
}
|
|
return true;
|
|
}
|
|
|
|
bool AABox::touches(const AABox& otherBox) const {
|
|
glm::vec3 relativeCenter = _corner - otherBox._corner + (glm::vec3(_scale - otherBox._scale) * 0.5f);
|
|
float totalHalfScale = 0.5f * (_scale + otherBox._scale);
|
|
return fabs(relativeCenter.x) <= totalHalfScale &&
|
|
fabs(relativeCenter.y) <= totalHalfScale &&
|
|
fabs(relativeCenter.z) <= totalHalfScale;
|
|
}
|
|
|
|
// determines whether a value is within the expanded extents
|
|
static bool isWithinExpanded(float value, float corner, float size, float expansion) {
|
|
return value >= corner - expansion && value <= corner + size + expansion;
|
|
}
|
|
|
|
bool AABox::expandedContains(const glm::vec3& point, float expansion) const {
|
|
return isWithinExpanded(point.x, _corner.x, _scale, expansion) &&
|
|
isWithinExpanded(point.y, _corner.y, _scale, expansion) &&
|
|
isWithinExpanded(point.z, _corner.z, _scale, expansion);
|
|
}
|
|
|
|
// finds the intersection between a ray and the facing plane on one axis
|
|
static bool findIntersection(float origin, float direction, float corner, float size, float& distance) {
|
|
if (direction > EPSILON) {
|
|
distance = (corner - origin) / direction;
|
|
return true;
|
|
} else if (direction < -EPSILON) {
|
|
distance = (corner + size - origin) / direction;
|
|
return true;
|
|
}
|
|
return false;
|
|
}
|
|
|
|
bool AABox::expandedIntersectsSegment(const glm::vec3& start, const glm::vec3& end, float expansion) const {
|
|
// handle the trivial cases where the expanded box contains the start or end
|
|
if (expandedContains(start, expansion) || expandedContains(end, expansion)) {
|
|
return true;
|
|
}
|
|
// check each axis
|
|
glm::vec3 expandedCorner = _corner - glm::vec3(expansion, expansion, expansion);
|
|
glm::vec3 expandedSize = glm::vec3(_scale, _scale, _scale) + glm::vec3(expansion, expansion, expansion) * 2.0f;
|
|
glm::vec3 direction = end - start;
|
|
float axisDistance;
|
|
return (findIntersection(start.x, direction.x, expandedCorner.x, expandedSize.x, axisDistance) &&
|
|
axisDistance >= 0.0f && axisDistance <= 1.0f &&
|
|
isWithin(start.y + axisDistance*direction.y, expandedCorner.y, expandedSize.y) &&
|
|
isWithin(start.z + axisDistance*direction.z, expandedCorner.z, expandedSize.z)) ||
|
|
(findIntersection(start.y, direction.y, expandedCorner.y, expandedSize.y, axisDistance) &&
|
|
axisDistance >= 0.0f && axisDistance <= 1.0f &&
|
|
isWithin(start.x + axisDistance*direction.x, expandedCorner.x, expandedSize.x) &&
|
|
isWithin(start.z + axisDistance*direction.z, expandedCorner.z, expandedSize.z)) ||
|
|
(findIntersection(start.z, direction.z, expandedCorner.z, expandedSize.z, axisDistance) &&
|
|
axisDistance >= 0.0f && axisDistance <= 1.0f &&
|
|
isWithin(start.y + axisDistance*direction.y, expandedCorner.y, expandedSize.y) &&
|
|
isWithin(start.x + axisDistance*direction.x, expandedCorner.x, expandedSize.x));
|
|
}
|
|
|
|
bool AABox::findRayIntersection(const glm::vec3& origin, const glm::vec3& direction, float& distance, BoxFace& face) const {
|
|
// handle the trivial case where the box contains the origin
|
|
if (contains(origin)) {
|
|
distance = 0;
|
|
return true;
|
|
}
|
|
// check each axis
|
|
float axisDistance;
|
|
if ((findIntersection(origin.x, direction.x, _corner.x, _scale, axisDistance) && axisDistance >= 0 &&
|
|
isWithin(origin.y + axisDistance*direction.y, _corner.y, _scale) &&
|
|
isWithin(origin.z + axisDistance*direction.z, _corner.z, _scale))) {
|
|
distance = axisDistance;
|
|
face = direction.x > 0 ? MIN_X_FACE : MAX_X_FACE;
|
|
return true;
|
|
}
|
|
if ((findIntersection(origin.y, direction.y, _corner.y, _scale, axisDistance) && axisDistance >= 0 &&
|
|
isWithin(origin.x + axisDistance*direction.x, _corner.x, _scale) &&
|
|
isWithin(origin.z + axisDistance*direction.z, _corner.z, _scale))) {
|
|
distance = axisDistance;
|
|
face = direction.y > 0 ? MIN_Y_FACE : MAX_Y_FACE;
|
|
return true;
|
|
}
|
|
if ((findIntersection(origin.z, direction.z, _corner.z, _scale, axisDistance) && axisDistance >= 0 &&
|
|
isWithin(origin.y + axisDistance*direction.y, _corner.y, _scale) &&
|
|
isWithin(origin.x + axisDistance*direction.x, _corner.x, _scale))) {
|
|
distance = axisDistance;
|
|
face = direction.z > 0 ? MIN_Z_FACE : MAX_Z_FACE;
|
|
return true;
|
|
}
|
|
return false;
|
|
}
|
|
|
|
bool AABox::findSpherePenetration(const glm::vec3& center, float radius, glm::vec3& penetration) const {
|
|
glm::vec4 center4 = glm::vec4(center, 1.0f);
|
|
|
|
float minPenetrationLength = FLT_MAX;
|
|
for (int i = 0; i < FACE_COUNT; i++) {
|
|
glm::vec4 facePlane = getPlane((BoxFace)i);
|
|
glm::vec3 vector = getClosestPointOnFace(center, (BoxFace)i) - center;
|
|
if (glm::dot(center4, getPlane((BoxFace)i)) >= 0.0f) {
|
|
// outside this face, so use vector to closest point to determine penetration
|
|
return ::findSpherePenetration(vector, glm::vec3(-facePlane), radius, penetration);
|
|
}
|
|
float vectorLength = glm::length(vector);
|
|
if (vectorLength < minPenetrationLength) {
|
|
// remember the smallest penetration vector; if we're inside all faces, we'll use that
|
|
penetration = (vectorLength < EPSILON) ? glm::vec3(-facePlane) * radius :
|
|
vector * ((vectorLength + radius) / -vectorLength);
|
|
minPenetrationLength = vectorLength;
|
|
}
|
|
}
|
|
|
|
return true;
|
|
}
|
|
|
|
bool AABox::findCapsulePenetration(const glm::vec3& start, const glm::vec3& end, float radius, glm::vec3& penetration) const {
|
|
glm::vec4 start4 = glm::vec4(start, 1.0f);
|
|
glm::vec4 end4 = glm::vec4(end, 1.0f);
|
|
glm::vec4 startToEnd = glm::vec4(end - start, 0.0f);
|
|
|
|
float minPenetrationLength = FLT_MAX;
|
|
for (int i = 0; i < FACE_COUNT; i++) {
|
|
// find the vector from the segment to the closest point on the face (starting from deeper end)
|
|
glm::vec4 facePlane = getPlane((BoxFace)i);
|
|
glm::vec3 closest = (glm::dot(start4, facePlane) <= glm::dot(end4, facePlane)) ?
|
|
getClosestPointOnFace(start4, startToEnd, (BoxFace)i) : getClosestPointOnFace(end4, -startToEnd, (BoxFace)i);
|
|
glm::vec3 vector = -computeVectorFromPointToSegment(closest, start, end);
|
|
if (glm::dot(vector, glm::vec3(facePlane)) < 0.0f) {
|
|
// outside this face, so use vector to closest point to determine penetration
|
|
return ::findSpherePenetration(vector, glm::vec3(-facePlane), radius, penetration);
|
|
}
|
|
float vectorLength = glm::length(vector);
|
|
if (vectorLength < minPenetrationLength) {
|
|
// remember the smallest penetration vector; if we're inside all faces, we'll use that
|
|
penetration = (vectorLength < EPSILON) ? glm::vec3(-facePlane) * radius :
|
|
vector * ((vectorLength + radius) / -vectorLength);
|
|
minPenetrationLength = vectorLength;
|
|
}
|
|
}
|
|
|
|
return true;
|
|
}
|
|
|
|
glm::vec3 AABox::getClosestPointOnFace(const glm::vec3& point, BoxFace face) const {
|
|
switch (face) {
|
|
case MIN_X_FACE:
|
|
return glm::clamp(point, glm::vec3(_corner.x, _corner.y, _corner.z),
|
|
glm::vec3(_corner.x, _corner.y + _scale, _corner.z + _scale));
|
|
|
|
case MAX_X_FACE:
|
|
return glm::clamp(point, glm::vec3(_corner.x + _scale, _corner.y, _corner.z),
|
|
glm::vec3(_corner.x + _scale, _corner.y + _scale, _corner.z + _scale));
|
|
|
|
case MIN_Y_FACE:
|
|
return glm::clamp(point, glm::vec3(_corner.x, _corner.y, _corner.z),
|
|
glm::vec3(_corner.x + _scale, _corner.y, _corner.z + _scale));
|
|
|
|
case MAX_Y_FACE:
|
|
return glm::clamp(point, glm::vec3(_corner.x, _corner.y + _scale, _corner.z),
|
|
glm::vec3(_corner.x + _scale, _corner.y + _scale, _corner.z + _scale));
|
|
|
|
case MIN_Z_FACE:
|
|
return glm::clamp(point, glm::vec3(_corner.x, _corner.y, _corner.z),
|
|
glm::vec3(_corner.x + _scale, _corner.y + _scale, _corner.z));
|
|
|
|
default: //quiet windows warnings
|
|
case MAX_Z_FACE:
|
|
return glm::clamp(point, glm::vec3(_corner.x, _corner.y, _corner.z + _scale),
|
|
glm::vec3(_corner.x + _scale, _corner.y + _scale, _corner.z + _scale));
|
|
}
|
|
}
|
|
|
|
glm::vec3 AABox::getClosestPointOnFace(const glm::vec4& origin, const glm::vec4& direction, BoxFace face) const {
|
|
// check against the four planes that border the face
|
|
BoxFace oppositeFace = getOppositeFace(face);
|
|
bool anyOutside = false;
|
|
for (int i = 0; i < FACE_COUNT; i++) {
|
|
if (i == face || i == oppositeFace) {
|
|
continue;
|
|
}
|
|
glm::vec4 iPlane = getPlane((BoxFace)i);
|
|
float originDistance = glm::dot(origin, iPlane);
|
|
if (originDistance < 0.0f) {
|
|
continue; // inside the border
|
|
}
|
|
anyOutside = true;
|
|
float divisor = glm::dot(direction, iPlane);
|
|
if (fabs(divisor) < EPSILON) {
|
|
continue; // segment is parallel to plane
|
|
}
|
|
// find intersection and see if it lies within face bounds
|
|
float directionalDistance = -originDistance / divisor;
|
|
glm::vec4 intersection = origin + direction * directionalDistance;
|
|
BoxFace iOppositeFace = getOppositeFace((BoxFace)i);
|
|
for (int j = 0; j < FACE_COUNT; j++) {
|
|
if (j == face || j == oppositeFace || j == i || j == iOppositeFace) {
|
|
continue;
|
|
}
|
|
if (glm::dot(intersection, getPlane((BoxFace)j)) > 0.0f) {
|
|
goto outerContinue; // intersection is out of bounds
|
|
}
|
|
}
|
|
return getClosestPointOnFace(glm::vec3(intersection), face);
|
|
|
|
outerContinue: ;
|
|
}
|
|
|
|
// if we were outside any of the sides, we must check against the diagonals
|
|
if (anyOutside) {
|
|
int faceAxis = face / 2;
|
|
int secondAxis = (faceAxis + 1) % 3;
|
|
int thirdAxis = (faceAxis + 2) % 3;
|
|
|
|
glm::vec4 secondAxisMinPlane = getPlane((BoxFace)(secondAxis * 2));
|
|
glm::vec4 secondAxisMaxPlane = getPlane((BoxFace)(secondAxis * 2 + 1));
|
|
glm::vec4 thirdAxisMaxPlane = getPlane((BoxFace)(thirdAxis * 2 + 1));
|
|
|
|
glm::vec4 offset = glm::vec4(0.0f, 0.0f, 0.0f,
|
|
glm::dot(glm::vec3(secondAxisMaxPlane + thirdAxisMaxPlane), glm::vec3(_scale, _scale, _scale)) * 0.5f);
|
|
glm::vec4 diagonals[] = { secondAxisMinPlane + thirdAxisMaxPlane + offset,
|
|
secondAxisMaxPlane + thirdAxisMaxPlane + offset };
|
|
|
|
float minDistance = FLT_MAX;
|
|
for (size_t i = 0; i < sizeof(diagonals) / sizeof(diagonals[0]); i++) {
|
|
float divisor = glm::dot(direction, diagonals[i]);
|
|
if (fabs(divisor) < EPSILON) {
|
|
continue; // segment is parallel to diagonal plane
|
|
}
|
|
minDistance = glm::min(-glm::dot(origin, diagonals[i]) / divisor, minDistance);
|
|
}
|
|
if (minDistance != FLT_MAX) {
|
|
return getClosestPointOnFace(glm::vec3(origin + direction * minDistance), face);
|
|
}
|
|
}
|
|
|
|
// last resort or all inside: clamp origin to face
|
|
return getClosestPointOnFace(glm::vec3(origin), face);
|
|
}
|
|
|
|
glm::vec4 AABox::getPlane(BoxFace face) const {
|
|
switch (face) {
|
|
case MIN_X_FACE: return glm::vec4(-1.0f, 0.0f, 0.0f, _corner.x);
|
|
case MAX_X_FACE: return glm::vec4(1.0f, 0.0f, 0.0f, -_corner.x - _scale);
|
|
case MIN_Y_FACE: return glm::vec4(0.0f, -1.0f, 0.0f, _corner.y);
|
|
case MAX_Y_FACE: return glm::vec4(0.0f, 1.0f, 0.0f, -_corner.y - _scale);
|
|
case MIN_Z_FACE: return glm::vec4(0.0f, 0.0f, -1.0f, _corner.z);
|
|
default: //quiet windows warnings
|
|
case MAX_Z_FACE: return glm::vec4(0.0f, 0.0f, 1.0f, -_corner.z - _scale);
|
|
}
|
|
}
|
|
|
|
BoxFace AABox::getOppositeFace(BoxFace face) {
|
|
switch (face) {
|
|
case MIN_X_FACE: return MAX_X_FACE;
|
|
case MAX_X_FACE: return MIN_X_FACE;
|
|
case MIN_Y_FACE: return MAX_Y_FACE;
|
|
case MAX_Y_FACE: return MIN_Y_FACE;
|
|
case MIN_Z_FACE: return MAX_Z_FACE;
|
|
default: //quiet windows warnings
|
|
case MAX_Z_FACE: return MIN_Z_FACE;
|
|
}
|
|
}
|