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mirror of https://gitlab.com/kicad/code/kicad.git synced 2024-11-24 00:34:47 +00:00
kicad/common/preview_items/item_drawing_utils.cpp
John Beard b2be0d39bd Snapping: Add construction geometry snapping
This is a pretty major rework of the snapping system.
The GRID_HELPERs now have a separate CONSTRUCTION_MANAGER
which handles some of the state involving "construction
geometry".

This is fed with 'extended' geometry (e.g. "infinite" lines from
segments) for use in generating things like intersection points.
It also handles adding this geoemtry to a GAL view item
(CONSTRUCTION_GEOM) for display to the user.

The process is:

* A TOOL creates a GRID_HELPER
* Optionally, it pre-loads a "persistent" batch of construction
  geometry (e.g. for an item's original position)
* The grid helper finds useful snap 'anchors' as before, including
  those involving the construction items.
* Other items on the board can be 'activated' by snapping to one
  of their main points. Then, if it has construction geometry,
  it will be added to the display. At most 2 items of this kind of
  geometry are shown, plus the original item, to reduce avoid
  too much clutter.

The dashed snap lines state machine is also handled in the
CONSTRUCTION_MANAGER and displayed in the CONSTRUCTION_GEOM item.
2024-09-11 22:35:35 +01:00

76 lines
2.6 KiB
C++

/*
* This program source code file is part of KICAD, a free EDA CAD application.
*
* Copyright (C) 2024 Kicad Developers, see AUTHORS.txt for contributors.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version 2
* of the License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, you may find one here:
* http://www.gnu.org/licenses/old-licenses/gpl-2.0.html
* or you may search the http://www.gnu.org website for the version 2 license,
* or you may write to the Free Software Foundation, Inc.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA
*/
#include "preview_items/item_drawing_utils.h"
#include <array>
#include <geometry/geometry_utils.h>
#include <geometry/seg.h>
using namespace KIGFX;
void KIGFX::DrawCross( GAL& aGal, const VECTOR2I& aPosition, int aSize )
{
const int size = aSize / 2;
aGal.DrawLine( aPosition - VECTOR2I( size, 0 ), aPosition + VECTOR2I( size, 0 ) );
aGal.DrawLine( aPosition - VECTOR2I( 0, size ), aPosition + VECTOR2I( 0, size ) );
}
void KIGFX::DrawDashedLine( GAL& aGal, const SEG& aSeg, double aDashSize )
{
const std::array<double, 2> strokes = { aDashSize, aDashSize / 2 };
const double dashCycleLen = strokes[0] + strokes[1];
// The dash cycle length must be at least 1 pixel.
wxASSERT( dashCycleLen * aGal.GetWorldScale() > 1 );
const BOX2I clip = BOX2I::ByCorners( aSeg.A, aSeg.B );
const double theta = atan2( aSeg.B.y - aSeg.A.y, aSeg.B.x - aSeg.A.x );
const VECTOR2D cycleVec{
dashCycleLen * cos( theta ),
dashCycleLen * sin( theta ),
};
const VECTOR2D dashVec{
strokes[0] * cos( theta ),
strokes[0] * sin( theta ),
};
unsigned cyclei = 0;
while( true )
{
const VECTOR2D dashStart = aSeg.A + cycleVec * cyclei;
const VECTOR2D dashEnd = dashStart + dashVec;
// Drawing each segment can be done rounded to ints.
SEG dashSeg{ KiROUND( dashStart ), KiROUND( dashEnd ) };
if( ClipLine( &clip, dashSeg.A.x, dashSeg.A.y, dashSeg.B.x, dashSeg.B.y ) )
break;
aGal.DrawLine( dashSeg.A, dashSeg.B );
++cyclei;
}
}