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Diffstat (limited to '')
-rw-r--r-- | src/display/drawing-context.cpp | 158 |
1 files changed, 158 insertions, 0 deletions
diff --git a/src/display/drawing-context.cpp b/src/display/drawing-context.cpp new file mode 100644 index 0000000..516202b --- /dev/null +++ b/src/display/drawing-context.cpp @@ -0,0 +1,158 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/** + * @file + * Cairo drawing context with Inkscape extensions. + *//* + * Authors: + * Krzysztof KosiĆski <tweenk.pl@gmail.com> + * + * Copyright (C) 2011 Authors + * Released under GNU GPL v2+, read the file 'COPYING' for more information. + */ + +#include "display/drawing-context.h" +#include "display/drawing-surface.h" +#include "display/cairo-utils.h" + +namespace Inkscape { + +using Geom::X; +using Geom::Y; + +/** + * @class DrawingContext::Save + * RAII idiom for saving the state of DrawingContext. + */ + +DrawingContext::Save::Save() + : _dc(nullptr) +{} +DrawingContext::Save::Save(DrawingContext &dc) + : _dc(&dc) +{ + _dc->save(); +} +DrawingContext::Save::~Save() +{ + if (_dc) { + _dc->restore(); + } +} +void DrawingContext::Save::save(DrawingContext &dc) +{ + if (_dc) { + // TODO: it might be better to treat this occurrence as a bug + _dc->restore(); + } + _dc = &dc; + _dc->save(); +} + +/** + * @class DrawingContext + * Minimal wrapper over Cairo. + * + * This is a wrapper over cairo_t, extended with operations that work + * with 2Geom geometrical primitives. Some of this is probably duplicated + * in cairo-render-context.cpp, which provides higher level operations + * for drawing entire SPObjects when exporting. + */ + +// Uses existing Cairo surface +DrawingContext::DrawingContext(cairo_t *ct, Geom::Point const &origin) + : _ct(ct) + , _surface(new DrawingSurface(cairo_get_group_target(ct), origin)) + , _delete_surface(true) + , _restore_context(true) +{ + _surface->_has_context = true; + cairo_reference(_ct); + cairo_save(_ct); + cairo_translate(_ct, -origin[Geom::X], -origin[Geom::Y]); +} + +// Uses existing Cairo surface +DrawingContext::DrawingContext(cairo_surface_t *surface, Geom::Point const &origin) + : _ct(nullptr) + , _surface(new DrawingSurface(surface, origin)) + , _delete_surface(true) + , _restore_context(false) +{ + _surface->_has_context = true; + _ct = _surface->createRawContext(); +} + +DrawingContext::DrawingContext(DrawingSurface &s) + : _ct(s.createRawContext()) + , _surface(&s) + , _delete_surface(false) + , _restore_context(false) +{} + +DrawingContext::~DrawingContext() +{ + if (_restore_context) { + cairo_restore(_ct); + } + cairo_destroy(_ct); + _surface->_has_context = false; + if (_delete_surface) { + delete _surface; + } +} + +void DrawingContext::arc(Geom::Point const ¢er, double radius, Geom::AngleInterval const &angle) +{ + double from = angle.initialAngle(); + double to = angle.finalAngle(); + if (to > from) { + cairo_arc(_ct, center[X], center[Y], radius, from, to); + } else { + cairo_arc_negative(_ct, center[X], center[Y], radius, to, from); + } +} + +// Applies transform to Cairo surface +void DrawingContext::transform(Geom::Affine const &trans) { + ink_cairo_transform(_ct, trans); +} + +void DrawingContext::path(Geom::PathVector const &pv) { + feed_pathvector_to_cairo(_ct, pv); +} + +void DrawingContext::paint(double alpha) { + if (alpha == 1.0) cairo_paint(_ct); + else cairo_paint_with_alpha(_ct, alpha); +} + +void DrawingContext::setHairline() { + ink_cairo_set_hairline(_ct); +} + +void DrawingContext::setSource(guint32 rgba) { + ink_cairo_set_source_rgba32(_ct, rgba); +} +void DrawingContext::setSource(DrawingSurface *s) { + Geom::Point origin = s->origin(); + cairo_set_source_surface(_ct, s->raw(), origin[X], origin[Y]); +} + +Geom::Rect DrawingContext::targetLogicalBounds() const +{ + Geom::Rect ret(_surface->area()); + return ret; +} + +} // end namespace Inkscape + +/* + Local Variables: + mode:c++ + c-file-style:"stroustrup" + c-file-offsets:((innamespace . 0)(inline-open . 0)(case-label . +)) + indent-tabs-mode:nil + fill-column:99 + End: +*/ +// vim: filetype=cpp:expandtab:shiftwidth=4:tabstop=8:softtabstop=4:fileencoding=utf-8:textwidth=99 : |