Skip to content

Commit

Permalink
Combine underwater and variation checks and apply to all planets whil…
Browse files Browse the repository at this point in the history 
…e relocating on all planets except for custom starports on planets where finding flat ground will not be very hard.
  • Loading branch information
@Ae-2222
Ae-2222 committed Sep 24, 2012
1 parent 86c0ddf commit b24d2e6
Showing 1 changed file with 89 additions and 87 deletions.
176 changes: 89 additions & 87 deletions src/Space.cpp
View file
Expand Up @@ -339,118 +339,120 @@ static void SetFrameOrientationFromSystemBodyAxialTilt(Frame *f, const SystemBod

static void RelocateStarportIfUnderwaterOrBuried(SystemBody *sbody, Frame *frame, Planet *planet, vector3d &pos, matrix4x4d &rot)
{
// check if underwater
int tries;
const double radius = planet->GetSystemBody()->GetRadius();

// first try suggested position
// suggested position
rot = sbody->orbit.rotMatrix;
pos = rot * vector3d(0,1,0);
double height = planet->GetTerrainHeight(pos) - radius;


bool isInitiallyUnderwater = false;
if (height <= 0.0) {
isInitiallyUnderwater = true;
MTRand r(sbody->seed);
// position is under water. try some random ones
for (tries=0; tries<100; tries++) {
// used for orientation on planet surface
double r2 = r.Double(); // function parameter evaluation order is implementation-dependent
double r1 = r.Double(); // can't put two rands in the same expression
rot = matrix4x4d::RotateZMatrix(2*M_PI*r1)
* matrix4x4d::RotateYMatrix(2*M_PI*r2);
pos = rot * vector3d(0,1,0);
height = planet->GetTerrainHeight(pos) - radius;
// don't want to be under water
if (height > 0.0) break;
}
}

if (isInitiallyUnderwater && sbody->isCustomBody) {
SystemPath &p = sbody->path;
fprintf(stderr, "Error: Lua custom Systems definition: Surface starport underwater. Please move the starport to another location by changing latitude and longitude fields.\n Surface starport name: %s, Body name: %s, In sector: x = %i, y = %i, z = %i.\n",
sbody->name.c_str(), sbody->parent->name.c_str(), p.sectorX, p.sectorY, p.sectorZ);
}

// For asteroids or bodies with large height variation relative to radius, check if height varies too much around the starport center
// Check if height varies too much around the starport center
// by sampling 6 points around it. try upto 100 new positions randomly until a match is found
// this is not guaranteed to find a match but greatly increases the chancessteroids which are not too steep.

bool variationWithinLimits = true;
double bestVariation = 1e10; // any high value
matrix4x4d rotWithLeastVariation;
vector3d posWithLeastVariation;
matrix4x4d rotNotUnderwaterWithLeastVariation = rot;
vector3d posNotUnderwaterWithLeastVariation = pos;
const double heightVariationCheckThreshold = 0.008; // max variation to radius radius ratio to check for local slope, ganymede is around 0.01
const double terrainHeightVariation = planet->GetGeoSphere()->GetMaxFeatureHeight(); //in radii

//printf("%s: terrain height variation %f\n", sbody->name.c_str(), terrainHeightVariation);

bool initialVariationTooHigh;
if (planet->GetSystemBody()->type == SystemBody::TYPE_PLANET_ASTEROID || terrainHeightVariation > heightVariationCheckThreshold) {
MTRand r(sbody->seed);

// 6 points are sampled around the starport center by adding/subtracting delta to to coords
// points must stay within max height variation to be accepted
// 1. delta should be chosen such that it a distance from the starport center that encloses landing pads for the largest starport
// 2. maxSlope should be set so maxHeightVariation is less than the height of the landing pads
const double delta = 20.0/radius; // in radii
const double maxSlope = 0.2; // 0.0 to 1.0
const double maxHeightVariation = maxSlope*delta*radius; // in m

for (tries = 0; tries < 100; tries++) {
variationWithinLimits = true;

// check height at 6 points around the starport center stays within variation tolerances
// GetHeight gives a varying height field in 3 dimensions.
// Given it's smoothly varying it's fine to sample it in arbitary directions to get an idea of how sharply it varies
double v[6];
v[0] = fabs(planet->GetTerrainHeight(vector3d(pos.x+delta, pos.y, pos.z))-radius-height);
v[1] = fabs(planet->GetTerrainHeight(vector3d(pos.x-delta, pos.y, pos.z))-radius-height);
v[2] = fabs(planet->GetTerrainHeight(vector3d(pos.x, pos.y, pos.z+delta))-radius-height);
v[3] = fabs(planet->GetTerrainHeight(vector3d(pos.x, pos.y, pos.z-delta))-radius-height);
v[4] = fabs(planet->GetTerrainHeight(vector3d(pos.x, pos.y+delta, pos.z))-radius-height);
v[5] = fabs(planet->GetTerrainHeight(vector3d(pos.x, pos.y-delta, pos.z))-radius-height);

// break if variation for all points is within limits
double variationMax = 0.0;
for (int i = 0; i < 6; i++) {
variationWithinLimits = variationWithinLimits && (v[i] < maxHeightVariation);
variationMax = (v[i] > variationMax)? v[i]:variationMax;
}
//printf("%s: try no: %i, Match found: %i, best variation in previous results %f, variationMax this try: %f, maxHeightVariation: %f\n",
// sbody->name.c_str(), tries, variationWithinLimits, bestVariation, variationMax, maxHeightVariation);
// 6 points are sampled around the starport center by adding/subtracting delta to to coords
// points must stay within max height variation to be accepted
// 1. delta should be chosen such that it a distance from the starport center that encloses landing pads for the largest starport
// 2. maxSlope should be set so maxHeightVariation is less than the height of the landing pads
const double delta = 20.0/radius; // in radii
const double maxSlope = 0.2; // 0.0 to 1.0
const double maxHeightVariation = maxSlope*delta*radius; // in m

if (variationWithinLimits) break;
matrix4x4d rot_ = rot;
vector3d pos_ = pos;

initialVariationTooHigh = true;
bool manualRelocationIsEasy = !(planet->GetSystemBody()->type == SystemBody::TYPE_PLANET_ASTEROID || terrainHeightVariation > heightVariationCheckThreshold);

if (variationMax < bestVariation) {
bestVariation = variationMax;
posWithLeastVariation = pos;
rotWithLeastVariation = rot;
}
// warn and leave it up to the user to relocate custom starports when it's easy to relocate manually, i.e. not on asteroids and other planets which are likely to have high variation in a lot of places
const bool isRelocatableIfBuried = !(sbody->isCustomBody && manualRelocationIsEasy);

// try new random position
double r2 = r.Double(); // function parameter evaluation order is implementation-dependent
double r1 = r.Double(); // can't put two rands in the same expression
rot = matrix4x4d::RotateZMatrix(2*M_PI*r1)
* matrix4x4d::RotateYMatrix(2*M_PI*r2);
pos = rot * vector3d(0,1,0);
height = planet->GetTerrainHeight(pos) - radius; // in m
bool isInitiallyUnderwater;
bool initialVariationTooHigh;

MTRand r(sbody->seed);

for (int tries = 0; tries < 200; tries++) {
variationWithinLimits = true;

const double height = planet->GetTerrainHeight(pos_) - radius; // in m

// check height at 6 points around the starport center stays within variation tolerances
// GetHeight gives a varying height field in 3 dimensions.
// Given it's smoothly varying it's fine to sample it in arbitary directions to get an idea of how sharply it varies
double v[6];
v[0] = fabs(planet->GetTerrainHeight(vector3d(pos_.x+delta, pos_.y, pos_.z))-radius-height);
v[1] = fabs(planet->GetTerrainHeight(vector3d(pos_.x-delta, pos_.y, pos_.z))-radius-height);
v[2] = fabs(planet->GetTerrainHeight(vector3d(pos_.x, pos_.y, pos_.z+delta))-radius-height);
v[3] = fabs(planet->GetTerrainHeight(vector3d(pos_.x, pos_.y, pos_.z-delta))-radius-height);
v[4] = fabs(planet->GetTerrainHeight(vector3d(pos_.x, pos_.y+delta, pos_.z))-radius-height);
v[5] = fabs(planet->GetTerrainHeight(vector3d(pos_.x, pos_.y-delta, pos_.z))-radius-height);

// break if variation for all points is within limits
double variationMax = 0.0;
for (int i = 0; i < 6; i++) {
variationWithinLimits = variationWithinLimits && (v[i] < maxHeightVariation);
variationMax = (v[i] > variationMax)? v[i]:variationMax;
}
if (!variationWithinLimits) {
pos = posWithLeastVariation;
rot = rotWithLeastVariation;

// check if underwater
const bool starportUnderwater = (height <= 0.0);

//printf("%s: try no: %i, Match found: %i, best variation in previous results %f, variationMax this try: %f, maxHeightVariation: %f, Starport is underwater: %i\n",
// sbody->name.c_str(), tries, (variationWithinLimits && !starportUnderwater), bestVariation, variationMax, maxHeightVariation, starportUnderwater);

if (tries == 0) {
isInitiallyUnderwater = starportUnderwater;
initialVariationTooHigh = !variationWithinLimits;
}
if (sbody->isCustomBody) {
SystemPath &p = sbody->path;
printf("Warning: Lua custom Systems definition: Surface starport has been automatically relocated. This is in order to place it on flatter ground to reduce the chance of landing pads being buried. This is not an error as such and you may attempt to move the starport to another location by changing latitude and longitude fields.\n Surface starport name: %s, Body name: %s, In sector: x = %i, y = %i, z = %i.\n",
sbody->name.c_str(), sbody->parent->name.c_str(), p.sectorX, p.sectorY, p.sectorZ);

if (!starportUnderwater && variationMax < bestVariation) {
bestVariation = variationMax;
posNotUnderwaterWithLeastVariation = pos_;
rotNotUnderwaterWithLeastVariation = rot_;
}

if (variationWithinLimits && !starportUnderwater) break;

// try new random position
const double r2 = r.Double(); // function parameter evaluation order is implementation-dependent
const double r1 = r.Double(); // can't put two rands in the same expression
rot_ = matrix4x4d::RotateZMatrix(2*M_PI*r1)
* matrix4x4d::RotateYMatrix(2*M_PI*r2);
pos_ = rot_ * vector3d(0,1,0);
}

if (isInitiallyUnderwater || (isRelocatableIfBuried && initialVariationTooHigh)) {
pos = posNotUnderwaterWithLeastVariation;
rot = rotNotUnderwaterWithLeastVariation;
}

if (sbody->isCustomBody) {
SystemPath &p = sbody->path;
if (initialVariationTooHigh) {
if (isRelocatableIfBuried) {
printf("Warning: Lua custom Systems definition: Surface starport has been automatically relocated. This is in order to place it on flatter ground to reduce the chance of landing pads being buried. This is not an error as such and you may attempt to move the starport to another location by changing latitude and longitude fields.\n Surface starport name: %s, Body name: %s, In sector: x = %i, y = %i, z = %i.\n",
sbody->name.c_str(), sbody->parent->name.c_str(), p.sectorX, p.sectorY, p.sectorZ);
} else {
printf("Warning: Lua custom Systems definition: Surface starport may have landing pads buried. The surface starport has not been automatically relocated as the planet appears smooth enough to manually relocate easily. This is not an error as such and you may attempt to move the starport to another location by changing latitude and longitude fields.\n Surface starport name: %s, Body name: %s, In sector: x = %i, y = %i, z = %i.\n",
sbody->name.c_str(), sbody->parent->name.c_str(), p.sectorX, p.sectorY, p.sectorZ);
}
}
if (isInitiallyUnderwater) {
fprintf(stderr, "Error: Lua custom Systems definition: Surface starport is underwater (height not greater than 0.0) and has been automatically relocated. Please move the starport to another location by changing latitude and longitude fields.\n Surface starport name: %s, Body name: %s, In sector: x = %i, y = %i, z = %i.\n",
sbody->name.c_str(), sbody->parent->name.c_str(), p.sectorX, p.sectorY, p.sectorZ);
}
}
}


static Frame *MakeFrameFor(SystemBody *sbody, Body *b, Frame *f)
{
Frame *orbFrame, *rotFrame;
Expand Down

0 comments on commit b24d2e6

Please sign in to comment.