// This function expects an integer width, not a meters width
void Template::addVerticalLine( int fromX, int fromY,
int destX, int destY, int width )
{
int ySign;
int x = fromX, y = fromY;
if( destY > fromY )
ySign = 1;
else
ySign = -1;
while( ySign*y <= destY )
{
if( x > 0 && x < mnXSize && y > 0 && y < mnYSize )
{
// the slope is 2 so that it will be considered more
// vertical than horizontal.
addWidth( x, y, width, 2 );
}
y += ySign;
}
if( destX > 0 && destX < mnXSize && destY > 0 && destY < mnYSize )
{
addWidth( destX, destY, width, 2 );
}
return;
} // End Function addVerticalLine
TCHAR *StreamParameters::addPrefix(TCHAR *dst, bool withPrecision) const {
*(dst++) = _T('%');
dst = addModifier(dst);
dst = addWidth(dst);
if(withPrecision) {
dst = addPrecision(dst);
}
return dst;
}
// Expects a width in meters
void Template::addSegment( const OGRPoint &from, const OGRPoint &dest,
double width )
{
int fromX, fromY, destX, destY; // begin and end coordinates
int x, y; // iterators
int xSign, ySign, slopeSign; // keep direction information
double slopeCount; // ghetto slope counter
double slope;
int iWidth = static_cast<int>( width * PIX_PER_METER );
// Determine what direction the line is going.
if( dest.getY() > from.getY() )
ySign = 1;
else
ySign = -1;
if( dest.getX() > from.getX() )
xSign = 1;
else
xSign = -1;
// Get starting and ending points in the raster coordinates.
fromX = static_cast<int>(from.getX() - mdXTrans);
fromY = static_cast<int>(from.getY() - mdYTrans);
destX = static_cast<int>(dest.getX() - mdXTrans);
destY = static_cast<int>(dest.getY() - mdYTrans);
// Calculate the slope. If the line is vertical then its
// slope is undefined so I need a different method. For
// that case I use the addVerticalLine function.
if( dest.getX() - from.getX() != 0 )
{
slope = (dest.getY() - from.getY()) /
(dest.getX() - from.getX());
if( slope >= 0 )
slopeSign = 1;
else
slopeSign = -1;
}
else
{
addVerticalLine( fromX, fromY, destX, destY, iWidth );
return;
}
// Start plotting the line
x = fromX;
y = fromY;
if( x < mnXSize && x >= 0 && y < mnYSize && y >= 0 )
{
addWidth( x, y, iWidth, slope );
}
// Plot the line, basically this just counts out rise over
// run like a fifth grader with some graph paper.
slopeCount = 0;
while( x != destX && y != destY )
{
if( slopeCount*slopeSign >= 1 )
{
y += ySign;
if( x < mnXSize && y < mnYSize )
{
addWidth( x, y, iWidth, slope );
}
slopeCount -= slopeSign;
}
else
{
x += xSign;
if( x < mnXSize && x >= 0 && y < mnYSize && y >= 0 )
{
addWidth( x, y, iWidth, slope );
}
slopeCount += slope;
}
}
// make sure the end point didn't get skipped over
if( destX < mnXSize && destX >= 0 && destY < mnYSize && destY >= 0 )
{
addWidth( destX, destY, iWidth, slope );
}
return;
} // End Function addSegment
