#5753: Merge pull request #21 from duzenko/5753_xy_zoom_cursor

XY View: use the mouse cursor position as base for zoom in/out instea…
codereader · Sep 17, 2021 · 7bbd03b · 7bbd03b
2 parents 8e1dafb + 606b6f5
commit 7bbd03b
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Showing 2 changed files with 28 additions and 19 deletions.
diff --git a/radiant/xyview/XYWnd.cpp b/radiant/xyview/XYWnd.cpp
@@ -1546,32 +1546,36 @@ void XYWnd::mouseToPoint(int x, int y, Vector3& point)
 // NOTE: the zoom out factor is 4/5, we could think about customizing it
 //  we don't go below a zoom factor corresponding to 10% of the max world size
 //  (this has to be computed against the window size)
+float XYWnd::getZoomedScale( int steps ) {
+    const float min_scale = std::min( getWidth(), getHeight() ) / ( 1.1f * ( _maxWorldCoord - _minWorldCoord ) );
+    const float max_scale = GlobalXYWnd().maxZoomFactor();
+    const float fZoom = pow( 5.0f / 4.0f, steps );
+    const float scale = getScale() * fZoom;
+    if ( scale > max_scale ) {
+        return max_scale;
+    }
+    if ( scale < min_scale ) {
+        return min_scale;
+    }
+    return scale;
+}
+
 void XYWnd::zoomOut()
 {
-    float min_scale = std::min(getWidth(),getHeight()) / ( 1.1f * (_maxWorldCoord - _minWorldCoord));
-    float scale = getScale() * 4.0f / 5.0f;
-    if (scale < min_scale) {
-        if (getScale() != min_scale) {
-            setScale(min_scale);
-        }
-    } else {
-        setScale(scale);
-    }
+    setScale( getZoomedScale( -1 ) );
 }
 
 void XYWnd::zoomIn()
 {
-    float max_scale = GlobalXYWnd().maxZoomFactor();
-    float scale = getScale() * 5.0f / 4.0f;
+    setScale( getZoomedScale( 1 ) );
+}
 
-    if (scale > max_scale) {
-        if (getScale() != max_scale) {
-            setScale(max_scale);
-        }
-    }
-    else {
-        setScale(scale);
-    }
+void XYWnd::zoomInOn( wxPoint cursor, int zoom ) {
+    const float oldScale = _scale;
+    const float newScale = getZoomedScale( zoom );
+    scroll( cursor.x - _width/2, _height / 2 - cursor.y );
+    setScale( newScale );
+    scroll( ( _width / 2 - cursor.x ) * oldScale / newScale, ( cursor.y - _height / 2 ) * oldScale / newScale );
 }
 
 // ================ CALLBACKS ======================================
@@ -1621,6 +1625,9 @@ bool XYWnd::onRender()
 
 void XYWnd::onGLWindowScroll(wxMouseEvent& ev)
 {
+    if ( !ev.ShiftDown() ) {
+        zoomInOn( ev.GetPosition(), ev.GetWheelRotation() / ev.GetWheelDelta() );
+    }
 	if (ev.GetWheelRotation() > 0)
 	{
 		zoomIn();

diff --git a/radiant/xyview/XYWnd.h b/radiant/xyview/XYWnd.h
@@ -133,8 +133,10 @@ class XYWnd :
 
     void mouseToPoint(int x, int y, Vector3& point);
 
+    float getZoomedScale( int steps );
     void zoomIn() override;
     void zoomOut() override;
+    void zoomInOn( wxPoint cursor, int zoom );
 
     void setActive(bool b);
     bool isActive() const;