Amebis/wxWidgets
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

Fixed setting clipping region for wxGCDC using device coordinates.

Browse Source 
Because source wxRegion contains regions given in device coordinates and underlying wxGraphicsContext::Clip() function expects regions in logical coordinates so we have to convert device coordinates of all region components to source coordinates prior to calling this function.

Effective clipping box (always calculated in logical units) is the result of intersection of clipping box of the provided region with either clipping box of previously set clipping region (if set) or with wxGCDC surface extents if no clipping region is set. This way effective clipping box is always inside the wxGCDC surface.
Note: Effective clipping box can be an empty region.

See #17596
This commit is contained in:
Artur Wieczorek
2016-07-15 21:00:49 +02:00
parent b2760ff420
commit 4e4317e71d
1 changed files with 52 additions and 23 deletions
Download Patch File Download Diff File Expand all files Collapse all files

75
src/common/dcgraph.cpp
View File

@@ -303,34 +303,63 @@ void wxGCDCImpl::DoSetDeviceClippingRegion( const wxRegion &region )
// region is in device coordinates
wxCHECK_RET( IsOk(), wxT("wxGCDC(cg)::DoSetDeviceClippingRegion - invalid DC") );
if (region.Empty())
// Convert device coordinates to logical coordinates
// for all region components.
wxRegion logRegion;
if ( region.IsEmpty() )
{
//DestroyClippingRegion();
return;
}
wxRegion logRegion( region );
wxCoord x, y, w, h;
logRegion.Offset( DeviceToLogicalX(0), DeviceToLogicalY(0) );
logRegion.GetBox( x, y, w, h );
m_graphicContext->Clip( logRegion );
if ( m_clipping )
{
m_clipX1 = wxMax( m_clipX1, x );
m_clipY1 = wxMax( m_clipY1, y );
m_clipX2 = wxMin( m_clipX2, (x + w) );
m_clipY2 = wxMin( m_clipY2, (y + h) );
// Empty region is skipped by iterator
// so we have to copy it directly.
logRegion = region;
}
else
{
m_clipping = true;
wxRegionIterator ri(region);
while (ri)
{
logRegion.Union(DeviceToLogicalX(ri.GetX()),
DeviceToLogicalY(ri.GetY()),
DeviceToLogicalXRel(ri.GetWidth()),
DeviceToLogicalYRel(ri.GetHeight()));
++ri;
}
}
m_clipX1 = x;
m_clipY1 = y;
m_clipX2 = x + w;
m_clipY2 = y + h;
m_graphicContext->Clip(logRegion);
wxRect newRegion = logRegion.GetBox();
wxRect clipRegion;
if ( m_clipping )
{
// New clipping box is an intersection
// of required clipping box and the current one.
wxRect curRegion(m_clipX1, m_clipY1, m_clipX2 - m_clipX1, m_clipY2 - m_clipY1);
clipRegion = curRegion.Intersect(newRegion);
}
else
{
// Effective clipping box is an intersection
// of required clipping box and DC surface.
int dcWidth, dcHeight;
DoGetSize(&dcWidth, &dcHeight);
wxRect dcRect(DeviceToLogicalX(0), DeviceToLogicalY(0),
DeviceToLogicalXRel(dcWidth), DeviceToLogicalYRel(dcHeight));
clipRegion = dcRect.Intersect(newRegion);
m_clipping = true;
}
if ( clipRegion.IsEmpty() )
{
m_clipX1 = m_clipY1 = m_clipX2 = m_clipY2 = 0;
}
else
{
m_clipX1 = clipRegion.GetLeft();
m_clipY1 = clipRegion.GetTop();
m_clipX2 = clipRegion.GetRight() + 1;
m_clipY2 = clipRegion.GetBottom() + 1;
}
}