ScreenProjection::ScreenProjection() :
_PanLat(MapWindow::GetPanLatitude()),
_PanLon(MapWindow::GetPanLongitude()),
_Zoom(MapWindow::GetDrawScale()),
_Angle(MapWindow::GetDisplayAngle()),
_Origin(MapWindow::GetOrigScreen()),
_CosAngle(ifastcosine(MapWindow::GetDisplayAngle())),
_SinAngle(ifastsine(MapWindow::GetDisplayAngle()))
{
}
void protateshift(POINT &pin, const double &angle, const int &xs, const int &ys) {
int x= pin.x;
int y= pin.y;
static double lastangle = 0;
static int cost=1024,sint=0;
if(angle != lastangle)
{
lastangle = angle;
cost = ifastcosine(angle);
sint = ifastsine(angle);
}
pin.x = (x*cost - y*sint + 512 + (xs*1024))/1024;
pin.y = (y*cost + x*sint + 512 + (ys*1024))/1024;
}
void irotate(int &xin, int &yin, const double &angle)
{
int x= xin;
int y= yin;
static double lastangle = 0;
static int cost=1024,sint=0;
if(angle != lastangle)
{
lastangle = angle;
cost = ifastcosine(angle);
sint = ifastsine(angle);
}
xin = (x*cost - y*sint + 512)/1024;
yin = (y*cost + x*sint + 512)/1024;
}
void irotatescale(int &xin, int &yin, const double &angle,
const double &scale, double &x, double &y)
{
static double lastangle = 0;
static double lastscale = 0;
static int cost=1024,sint=0;
if((angle != lastangle)||(scale != lastscale))
{
lastscale = scale/1024;
lastangle = angle;
cost = ifastcosine(angle);
sint = ifastsine(angle);
}
x = (xin*cost - yin*sint + 512)*lastscale;
y = (yin*cost + xin*sint + 512)*lastscale;
}
void threadsafePolygonRotateShift(POINT* poly, const int n, const int xs, const int ys, const double angle) {
const int cost = ifastcosine(angle)*ScreenScale;
const int sint = ifastsine(angle)*ScreenScale;
const int xxs = xs*1024+512;
const int yys = ys*1024+512;
POINT *p = poly;
const POINT *pe = poly+n;
while (p<pe) {
int x= p->x;
int y= p->y;
p->x = (x*cost - y*sint + xxs)/1024;
p->y = (y*cost + x*sint + yys)/1024;
p++;
}
}
void protate(POINT &pin, const double &angle)
{
int x= pin.x;
int y= pin.y;
static double lastangle = 0;
static int cost=1024,sint=0;
if(angle != lastangle)
{
lastangle = angle;
cost = ifastcosine(angle);
sint = ifastsine(angle);
}
pin.x = (x*cost - y*sint + 512 )/1024;
pin.y = (y*cost + x*sint + 512 )/1024;
// round (x/b) = (x+b/2)/b;
// b = 2; x = 10 -> (10+1)/2=5
// b = 2; x = 11 -> (11+1)/2=6
// b = 2; x = -10 -> (-10+1)/2=4
}
//
// This function must be reinitialised on resolution change
// THIS FUNCTION IS NOT THREAD SAFE AND CANNOT BE USED OUTSIDE DRAW THREAD
//
void PolygonRotateShift(POINT* poly, const int n, const int xs, const int ys, const double angle) {
static double lastangle = -1;
static int cost=1024, sint=0;
if(angle != lastangle) {
lastangle = angle;
cost = ifastcosine(angle)*ScreenScale;
sint = ifastsine(angle)*ScreenScale;
}
const int xxs = xs*1024+512;
const int yys = ys*1024+512;
POINT *p = poly;
const POINT *pe = poly+n;
while (p<pe) {
int x= p->x;
int y= p->y;
p->x = (x*cost - y*sint + xxs)/1024;
p->y = (y*cost + x*sint + yys)/1024;
p++;
}
}