//------------------------------------------------------------------------------
// converts screen to lat/lon coordinates
//------------------------------------------------------------------------------
bool MapPage::screen2LatLon(const LCreal x, const LCreal y,
double* const lat, double* const lon) const
{
bool ok = false;
const double scale = getScale();
const double cosLat = getCosRefLat();
if (lat != nullptr && lon != nullptr && scale != 0 && cosLat != 0) {
// buffer the inputs
double screenX = x;
double screenY = y;
// Adjust for the decentered displayment
if ( !getCentered() ) screenY -= getDisplacement();
// Scale from screen (inches) to A/C (NM) and
// transpose the X and Y from screen to A/C
const double acX = screenY/scale;
const double acY = screenX/scale;
// Rotate A/C to NED
double earthX = 0.0;
double earthY = 0.0;
if (getNorthUp()) {
earthX = acX;
earthY = acY;
}
else {
earthX = (acX * headingCos) - (acY * headingSin);
earthY = (acX * headingSin) + (acY * headingCos);
}
// Convert nautical miles (NED) from ref point to lat/lon
*lat = (earthX/60.0) + getReferenceLatDeg();
*lon = (earthY/(60.0*cosLat)) + getReferenceLonDeg();
ok = true;
}
return ok;
}
//------------------------------------------------------------------------------
// converts lat/lon to screen coordinates
//------------------------------------------------------------------------------
bool MapPage::latLon2Screen(const double lat, const double lon,
LCreal* const x, LCreal* const y) const
{
bool ok = false;
if (x != nullptr && y != nullptr) {
// Convert to nautical miles (NED) centered on ownship
const double earthX = ((lat - getReferenceLatDeg()) * 60.0);
const double earthY = ((lon - getReferenceLonDeg()) * 60.0 * getCosRefLat());
// Rotate to aircraft coordinates
double acX = 0;
double acY = 0;
if (getNorthUp()) {
acX = earthX;
acY = earthY;
}
else {
acX = (earthX * headingCos) + (earthY * headingSin);
acY = -(earthX * headingSin) + (earthY * headingCos);
}
// Scale from nautical miles to inches and
// transpose the X and Y from A/C to screen
double screenY = acX * getScale();
const double screenX = acY * getScale();
// Adjust for the decentered displayment
if ( !getCentered() ) screenY += getDisplacement();
*x = static_cast<LCreal>(screenX);
*y = static_cast<LCreal>(screenY);
ok = true;
}
return ok;
}
//------------------------------------------------------------------------------
// drawFunc() - Draw the map.
//------------------------------------------------------------------------------
void MapDrawer::drawFunc()
{
GLdouble ocolor[4];
// Get our old color
glGetDoublev(GL_CURRENT_COLOR, &ocolor[0]);
GLdouble dLeft = 0, dRight = 0, dBottom = 0, dTop = 0, dNear = 0, dFar = 0;
//double lat = 0, lon = 0;
// Determine our rotation, if needed.
if (getDisplay() != 0) getDisplay()->getOrtho(dLeft, dRight, dBottom, dTop, dNear, dFar);
if (myMap != 0) {
double rLat = myMap->getReferenceLatDeg();
double rLon = myMap->getReferenceLonDeg();
int refZone = myMap->findBestZone(rLat, rLon);
if (refZone != -1) {
// Determine our CENTER tile and pixel position
myMap->latLonToTileRowColumn(rLat, rLon, originRow[CENTER_PAGER], originCol[CENTER_PAGER], textureRow[CENTER_PAGER], textureCol[CENTER_PAGER], pixelRow[CENTER_PAGER], \
pixelCol[CENTER_PAGER], pagers[CENTER_PAGER]);
// Take the distance in nautical miles, and then convert to degrees
LCreal quickRange = getRange();
LCreal disDegN = quickRange / 60.0f;
LCreal disDegE = (LCreal)(quickRange / (60.0 * getCosRefLat()));
// Get the space (in latitude degrees) between each pixel
CadrgTocEntry* te = pagers[CENTER_PAGER]->getToc();
LCreal n = 1, e = 1;
if (te != 0) {
n = (LCreal)te->getVertInterval();
e = (LCreal)te->getHorizInterval();
}
// OK, so we know how far we want to look out (disDeg, and how far it is per pixel, so we can find
// the total amount of pixels by dividing disDeg / x.
vpHL = disDegN / n;
vpWL = disDegE / e;
// Scale our viewport by the ratio of our map page to our actual ortho, to make our background map fit into our range circle
LCreal rad = getOuterRadius();
LCreal radRatio = (LCreal)(dTop / rad);
vpHL *= radRatio;
vpWL *= radRatio;
// Now stretch and shrink our ortho based on if we are track up
double newVPHL = vpHL;
double newVPWL = vpWL;
// Force our ortho before drawing
getDisplay()->forceOrtho(-newVPWL, newVPWL, -newVPHL, newVPHL, -2, 2);
// Update our current reference zone
updateZone(refZone, zones[CENTER_PAGER], CENTER_PAGER);
// Tell our center pager to draw the map
drawMap(zones[CENTER_PAGER], CENTER_PAGER);
// Check to see if we need to have zones around us (depending on the range)
LCreal rngDeg = (quickRange * 2) / 60.0f;
int tZone = myMap->findBestZone(rLat + rngDeg, rLon);
// Now determine if there are other zones to draw
if (tZone != zones[CENTER_PAGER]) {
updateZone(tZone, zones[TOP_PAGER], TOP_PAGER);
myMap->latLonToTileRowColumn(rLat, rLon, originRow[TOP_PAGER], originCol[TOP_PAGER], textureRow[TOP_PAGER], textureCol[TOP_PAGER], pixelRow[TOP_PAGER], \
pixelCol[TOP_PAGER], pagers[TOP_PAGER]);
// Draw the map
drawMap(zones[TOP_PAGER], TOP_PAGER);
}
else pagers[TOP_PAGER]->flushTextures();
// Set our reference zone.
myMap->setZone(zones[CENTER_PAGER], pagers[CENTER_PAGER]);
}
}
// Set our ortho and our color back to it's original state after we draw.
getDisplay()->forceOrtho(dLeft, dRight, dBottom, dTop, dNear, dFar);
glColor4dv(ocolor);
}
