kicad/common/dpi_scaling.cpp

178 lines
4.3 KiB
C++

/*
* This program source code file is part of KiCad, a free EDA CAD application.
*
* Copyright (C) 2019 KiCad Developers, see CHANGELOG.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 <dpi_scaling.h>
#include <core/optional.h>
#include <env_vars.h>
#include <pgm_base.h>
#include <wx/config.h>
#include <wx/log.h>
/**
* Flag to enable trace for HiDPI scaling factors
*
* Use "KICAD_TRACE_HIGH_DPI" to enable.
*
* @ingroup trace_env_vars
*/
const wxChar* const traceHiDpi = wxT( "KICAD_TRACE_HIGH_DPI" );
/**
* Get a user-configured scale factor from KiCad config file
*
* @return the scale factor, if set
*/
static OPT<double> getKiCadConfiguredScale( const wxConfigBase& aConfig )
{
OPT<double> scale;
double canvas_scale = 0.0;
aConfig.Read( CANVAS_SCALE_KEY, &canvas_scale, 0.0 );
if( canvas_scale > 0.0 )
{
scale = canvas_scale;
}
if( scale )
{
wxLogTrace( traceHiDpi, "Scale factor (configured): %f", *scale );
}
return scale;
}
/**
* Get the toolkit scale factor from a user-set environment variable
* (for example GDK_SCALE on GTK).
*
* @return the scale factor, if set
*/
static OPT<double> getEnviromentScale()
{
const wxPortId port_id = wxPlatformInfo::Get().GetPortId();
OPT<double> scale;
if( port_id == wxPORT_GTK )
{
// Under GTK, the user can use GDK_SCALE to force the scaling
scale = GetEnvVar<double>( "GDK_SCALE" );
}
if( scale )
{
wxLogTrace( traceHiDpi, "Scale factor (environment): %f", *scale );
}
return scale;
}
DPI_SCALING::DPI_SCALING( wxConfigBase* aConfig, const wxWindow* aWindow )
: m_config( aConfig ), m_window( aWindow )
{
}
double DPI_SCALING::GetScaleFactor() const
{
OPT<double> val;
if( m_config )
{
val = getKiCadConfiguredScale( *m_config );
}
if( !val )
{
val = getEnviromentScale();
}
if( !val && m_window )
{
// Use the native WX reporting.
// On Linux, this will not work until WX 3.2 and GTK >= 3.10
// Otherwise it returns 1.0
val = m_window->GetContentScaleFactor();
wxLogTrace( traceHiDpi, "Scale factor (WX): %f", *val );
}
if( !val )
{
// Nothing else we can do, give it a default value
val = GetDefaultScaleFactor();
wxLogTrace( traceHiDpi, "Scale factor (default): %f", *val );
}
return *val;
}
bool DPI_SCALING::GetCanvasIsAutoScaled() const
{
if( m_config == nullptr )
{
// No configuration given, so has to be automatic scaling
return true;
}
const bool automatic = getKiCadConfiguredScale( *m_config ) == boost::none;
wxLogTrace( traceHiDpi, "Scale is automatic: %d", automatic );
return automatic;
}
void DPI_SCALING::SetDpiConfig( bool aAuto, double aValue )
{
wxCHECK_RET( m_config != nullptr, "Setting DPI config without a config store." );
const double value = aAuto ? 0.0 : aValue;
m_config->Write( CANVAS_SCALE_KEY, value );
}
double DPI_SCALING::GetMaxScaleFactor()
{
// displays with higher than 4.0 DPI are not really going to be useful
// for KiCad (even an 8k display would be effectively only ~1080p at 4x)
return 6.0;
}
double DPI_SCALING::GetMinScaleFactor()
{
// scales under 1.0 don't make sense from a HiDPI perspective
return 1.0;
}
double DPI_SCALING::GetDefaultScaleFactor()
{
// no scaling => 1.0
return 1.0;
}