[Kstars-devel] branches/work/kdeedu_kstars_htm/kstars/kstars/skycomponents
James Bowlin
bowlin at mindspring.com
Wed Aug 8 08:53:51 CEST 2007
SVN commit 697607 by jbowlin:
I've re-implemented the Ecliptic and Equator labels. I'm doing it
slightly differently. I still try to put "Equator" on the left side
of the screen and "Ecliptic" on the right but I put a little more
emphasis on keeping the labels more horizontal than vertical. It's
not perfect but I think it looks pretty good. We could probably tweak
it so it puts more emphasis on left/right if that is desired.
The current code could probably be ported to the trunk with only minor
changes.
I think I'm now prepared to add these two components to the index.
Another direction to go in is to try to prevent label overlap. I
don't see an easy way to prevent the "Ecliptic" and "Equator" labels
from overlapping each other but it would probably be pretty easy to
prevent all the other labels from overlapping those two.
CCMAIL: kstars-devel at kde.org
M +112 -119 linelistcomponent.cpp
M +12 -1 linelistcomponent.h
--- branches/work/kdeedu_kstars_htm/kstars/kstars/skycomponents/linelistcomponent.cpp #697606:697607
@@ -26,11 +26,14 @@
#include "skymap.h"
#include "dms.h"
#include "Options.h"
+#include "skylabeler.h"
LineListComponent::LineListComponent( SkyComponent *parent )
: SkyComponent( parent ), LabelPosition( NoLabel ), Label( QString() )
-{}
+{
+ m_skyLabeler = ((SkyMapComposite*) parent)->skyLabeler();
+}
LineListComponent::~LineListComponent()
{}
@@ -46,7 +49,8 @@
}
}
-void LineListComponent::draw( KStars *ks, QPainter &psky, double scale ) {
+void LineListComponent::draw( KStars *ks, QPainter &psky, double scale )
+{
if ( ! selected() ) return;
SkyMap *map = ks->map();
@@ -56,15 +60,28 @@
bool isVisible, isVisibleLast;
SkyPoint *pLast, *pThis;
- QList<QPointF> pList; // for sending to drawLabels()
+ float xLeft = 100000.;
+ float xRight = 0.;
+ float yTop = 100000.;
+ float yBot = 0.;
+ m_skyLabeler->useStdFont( psky );
+ QFontMetricsF fm( psky.font() );
+ m_skyLabeler->resetFont( psky );
+ float margin = fm.width("MMM");
+ float rightMargin = psky.window().width() - margin - fm.width( Label );
+ float leftMargin = margin;
+ float topMargin = fm.height();
+ float botMargin = psky.window().height() - 4.0 * fm.height();
+
+ m_iLeft = m_iRight = m_iTop = m_iBot = 0;
+
if ( Options::useAntialias() ) {
QPointF oThis, oLast, oMid;
pLast = points()->at( 0 );
-
oLast = map->toScreen( pLast, scale, false, &isVisibleLast );
int limit = points()->size();
@@ -76,11 +93,33 @@
if ( map->onScreen(oThis, oLast ) ) {
if ( isVisible && isVisibleLast ) {
psky.drawLine( oLast, oThis );
+
+ qreal x = oThis.x();
+ qreal y = oThis.y();
+ if ( x > leftMargin && x < rightMargin &&
+ y < botMargin && y > topMargin) {
+
+ if ( x < xLeft ) {
+ m_iLeft = i;
+ xLeft = x;
+ }
+ if ( x > xRight ) {
+ m_iRight = i;
+ xRight = x;
+ }
+ if ( y > yBot ) {
+ m_iBot = i;
+ yBot = y;
+ }
+ if ( y < yTop ) {
+ m_iTop = i;
+ yTop = y;
+ }
+ }
}
else if ( isVisibleLast && ! isVisible ) {
oMid = map->clipLine( pLast, pThis, scale );
- // -jbb printf("oMid: %4d %4d\n", oMid.x(), oMid.y());
psky.drawLine( oLast, oMid );
}
else if ( isVisible && ! isVisibleLast ) {
@@ -111,7 +150,6 @@
if ( isVisible && isVisibleLast ) {
psky.drawLine( oLast.x(), oLast.y(), oThis.x(), oThis.y() );
}
-
else if ( isVisibleLast ) {
oMid = map->clipLineI( pLast, pThis, scale );
// -jbb printf("oMid: %4d %4d\n", oMid.x(), oMid.y());
@@ -128,136 +166,91 @@
isVisibleLast = isVisible;
}
}
-}
-/***********************************
- //Each SkyLine is a series of line segments in the celestial coordinate system.
- //Transform each segment to screen coordinates, and draw the segments that are on-screen
- pList = map->toScreen( &m_SkyLine, scale, Options::useRefraction(), true) //clip offscreen segments );
- //highZoomFactor = true when FOV is less than 1 degree (1/57.3 radians)
- bool highZoomFactor( false );
- if ( Options::zoomFactor() > map->width()*57.3 )
- highZoomFactor = true;
-
- QPointF pLast( -10000000., -10000000. );
- foreach ( QPointF p, pList ) {
- if ( ! map->isPointNull( pLast ) && ! map->isPointNull( p ) ) {
-
- if ( fabs(p.x()-pLast.x()) < map->width() || highZoomFactor )
- psky.drawLine( pLast, p );
-
-*********************************/
-/********
- //Next, identify the index of the point whose segment brackets
- //the left-edge position (x=20), the right-edge position (x=width()-60),
- //the top-edge position (y=20), and the bottom-edge pos. (y=height()-30)
- float xLeft = 20.;
- float xRight = psky.window().width() - 60.;
- float yTop = 20.;
- float yBottom = psky.window().height() - 30.;
- if ( (p.x() >= xLeft && pLast.x() < xLeft) || (pLast.x() >= xLeft && p.x() < xLeft) )
- iLeft = pList.indexOf( p );
- if ( (p.x() >= xRight && pLast.x() < xRight) || (pLast.x() >= xRight && p.x() < xRight) )
- iRight = pList.indexOf( p );
- if ( (p.y() >= yTop && pLast.y() < yTop) || (pLast.y() >= yTop && p.y() < yTop) )
- iTop = pList.indexOf( p );
- if ( (p.y() >= yBottom && pLast.y() < yBottom) || (pLast.y() >= yBottom && p.y() < yBottom) )
- iBottom = pList.indexOf( p );
- }
- pLast = p;
- drawLabels(ks, psky, scale, pList);
- }
+ drawLabels( ks, psky, scale );
}
-********/
+void LineListComponent::drawLabels( KStars* kstars, QPainter& psky, double scale )
+{
-void LineListComponent::drawLabels( KStars *ks, QPainter &psky, double scale, QList<QPointF> &pList ) {
+ if ( LabelPosition == NoLabel ) return;
- int iLeft = -1; //the segment that intersects the left edge
- int iRight = -1; //the segment that intersects the right edge
- int iTop = -1; //the segment that intersects the top edge
- int iBottom = -1; //the segment that intersects the bottom edge
+ int i[4];
+ double a[4] = { 360.0, 360.0, 360.0, 360.0 };
+ QPointF o[4];
- //Now label the LineListComponent. We have stored the index of line segments
- //near each edge of the screen. Draw the label near one of these segments,
- //according to the value of LabelPosition
- if ( LabelPosition != NoLabel ) {
- //Make sure we have at least one edge segment defined
- if ( iLeft < 0 && iRight < 0 && iTop < 0 && iBottom < 0 ) return;
+ if ( LabelPosition == LeftEdgeLabel ) {
+ i[0] = m_iLeft;
+ i[1] = m_iTop;
+ i[2] = m_iBot;
+ i[3] = m_iRight;
+ }
+ else {
+ i[0] = m_iRight;
+ i[1] = m_iBot;
+ i[2] = m_iTop;
+ i[3] = m_iLeft;
+ }
- //Draw the label at segLeft or segRight. If this segment is undefined,
- //choose segTop or segBottom, wheichever is further left or right
- int iLabel;
- double tx;
- double ty;
+ // Make sure we have at least one valid point
+ for ( int j = 1; j < 4; j++) {
+ if ( i[0] ) break;
+ i[0] = i[j];
+ }
+ if ( i[0] == 0 ) return;
- if ( LabelPosition == LeftEdgeLabel ) {
- if ( iLeft >= 0 ) {
- iLabel = iLeft;
- tx = 20.0;
- ty = pList[iLabel].y() - 5.0;
+ SkyMap *map = kstars->map();
+ double comfyAngle = 45.0;
- //if iLeft is undefined, try the top or bottom edge, whichever is further left
- } else {
- if ( iTop >= 0 && iBottom >= 0 ) {
- if ( pList[iTop].x() < pList[iBottom].x() )
- iLabel = iTop;
- else
- iLabel = iBottom;
- } else if ( iTop >= 0 ) {
- iLabel = iTop;
+ // Try the points in order and print the label if we can draw it at
+ // a comfortable angle for viewing;
- } else if ( iBottom >= 0 ) {
- iLabel = iBottom;
- }
- //FIXME: -jbb to prevent crashes on index out of range
-
- //tx = pList[iLabel].x();
- //ty = pList[iLabel].y() - 5.0;
- }
+ for ( int j = 0; j < 4; j++) {
+ o[j] = angleAt( map, i[j], &a[j], scale );
+ //printf("a[%d]=%.f ", j, a[j]);
+ if ( fabs( a[j] ) < comfyAngle ) {
+ //printf("\n");
+ return drawTheLabel( psky, o[j], a[j] );
}
+ }
+ //printf("\n");
- if ( LabelPosition == RightEdgeLabel ) {
- if ( iRight >= 0 ) {
- iLabel = iRight;
- tx = psky.window().width() - 60.0;
- ty = pList[iLabel].y() - 5.0;
+ // No angle was great so pick the best angle
+ int ii = 0;
+ for ( int j = 1; j < 4; j++) {
+ if ( fabs(a[j]) < fabs(a[ii]) ) ii = j;
+ }
- //if iRight is undefined, try the top or bottom edge, whichever is further right
- } else {
- if ( iTop >= 0 && iBottom >= 0 ) {
- if ( pList[iTop].x() > pList[iBottom].x() )
- iLabel = iTop;
- else
- iLabel = iBottom;
- } else if ( iTop >= 0 ) {
- iLabel = iTop;
+ return drawTheLabel( psky, o[ii], a[ii] );
+}
- } else if ( iBottom >= 0 ) {
- iLabel = iBottom;
- }
+void LineListComponent::drawTheLabel( QPainter& psky, QPointF& o, double angle )
+{
+ m_skyLabeler->useStdFont( psky );
+ QFontMetricsF fm( psky.font() );
- //FIXME: -jbb to prevent crashes on index out of range
+ psky.save();
+ psky.translate( o );
- //tx = pList[iLabel].x();
- //ty = pList[iLabel].y() - 5.0;
- }
- }
+ psky.rotate( double( angle ) ); //rotate the coordinate system
+ psky.drawText( QPointF( 0., fm.height() ), Label );
+ psky.restore(); //reset coordinate system
- if ( iLabel == 0 )
- iLabel = 1;
+ m_skyLabeler->resetFont( psky );
+}
+QPointF LineListComponent::angleAt( SkyMap* map, int i, double *angle, double scale )
+{
+ SkyPoint* pThis = points()->at( i );
+ SkyPoint* pLast = points()->at( i - 1 );
+ QPointF oThis = map->toScreen( pThis, scale, false );
+ QPointF oLast = map->toScreen( pLast, scale, false );
+ double sx = double( oThis.x() - oLast.x() );
+ double sy = double( oThis.y() - oLast.y() );
+ *angle = atan2( sy, sx ) * 180.0 / dms::PI;
+ if ( *angle < -90.0 ) *angle += 180.0;
+ if ( *angle > 90.0 ) *angle -= 180.0;
+ return oThis;
+}
- //double sx = double( pList[iLabel].x() - pList[iLabel-1].x() );
- //double sy = double( pList[iLabel].y() - pList[iLabel-1].y() );
- //double angle = atan2( sy, sx )*180.0/dms::PI;
- //if ( sx < 0.0 ) angle -= 180.0;
- //psky.save();
- // FIXME: -jbb psky.translate( tx, ty );
-
- //psky.rotate( double( angle ) ); //rotate the coordinate system
- //psky.drawText( 0, 0, Label );
- //psky.restore(); //reset coordinate system
- }
-}
--- branches/work/kdeedu_kstars_htm/kstars/kstars/skycomponents/linelistcomponent.h #697606:697607
@@ -28,6 +28,8 @@
#include "skypoint.h"
class KStars;
+class SkyLabeler;
+class SkyMap;
/**
*@class LineListComponent
@@ -59,8 +61,9 @@
/**Draw the list of objects on the SkyMap*/
virtual void draw( KStars *ks, QPainter& psky, double scale );
- void drawLabels( KStars *ks, QPainter &psky, double scale, QList<QPointF> &pList );
+ void drawLabels( KStars* kstars, QPainter& psky, double scale );
+
/**Draw the object, if it is exportable to an image
*@see isExportable()
*/
@@ -93,6 +96,14 @@
int LabelPosition;
QString Label;
QPen Pen;
+
+ SkyLabeler* m_skyLabeler;
+ //int m_labelIndex[4];
+ int m_iLeft, m_iRight, m_iTop, m_iBot;
+
+ QPointF angleAt( SkyMap* map, int i, double *angle, double scale );
+
+ void drawTheLabel( QPainter& psky, QPointF& o, double angle );
};
#endif
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