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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:24:48 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:24:48 +0000
commitcca66b9ec4e494c1d919bff0f71a820d8afab1fa (patch)
tree146f39ded1c938019e1ed42d30923c2ac9e86789 /src/display/control/canvas-item-curve.cpp
parentInitial commit. (diff)
downloadinkscape-upstream.tar.xz
inkscape-upstream.zip
Adding upstream version 1.2.2.upstream/1.2.2upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to '')
-rw-r--r--src/display/control/canvas-item-curve.cpp236
1 files changed, 236 insertions, 0 deletions
diff --git a/src/display/control/canvas-item-curve.cpp b/src/display/control/canvas-item-curve.cpp
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+++ b/src/display/control/canvas-item-curve.cpp
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+// SPDX-License-Identifier: GPL-2.0-or-later
+/**
+ * A class to represent a single Bezier control curve, either a line or a cubic Bezier.
+ */
+
+/*
+ * Author:
+ * Tavmjong Bah
+ *
+ * Copyright (C) 2020 Tavmjong Bah
+ *
+ * Rewrite of SPCtrlLine and SPCtrlCurve
+ *
+ * Released under GNU GPL v2+, read the file 'COPYING' for more information.
+ */
+
+#include <2geom/bezier-curve.h>
+
+#include "canvas-item-curve.h"
+
+#include "color.h" // SP_RGBA_x_F
+
+#include "ui/widget/canvas.h"
+
+namespace Inkscape {
+
+/**
+ * Create an null control curve.
+ */
+CanvasItemCurve::CanvasItemCurve(CanvasItemGroup *group)
+ : CanvasItem(group)
+{
+ _name = "CanvasItemCurve:Null";
+ _pickable = false; // For now, nobody gets events from this class!
+}
+
+/**
+ * Create a linear control curve. Points are in document coordinates.
+ */
+CanvasItemCurve::CanvasItemCurve(CanvasItemGroup *group, Geom::Point const &p0, Geom::Point const &p1)
+ : CanvasItem(group)
+ , _curve(std::make_unique<Geom::LineSegment>(p0, p1))
+{
+ _name = "CanvasItemCurve:Line";
+ _pickable = false; // For now, nobody gets events from this class!
+
+ request_update();
+}
+
+/**
+ * Create a cubic Bezier control curve. Points are in document coordinates.
+ */
+CanvasItemCurve::CanvasItemCurve(CanvasItemGroup *group,
+ Geom::Point const &p0, Geom::Point const &p1,
+ Geom::Point const &p2, Geom::Point const &p3)
+ : CanvasItem(group)
+ , _curve(std::make_unique<Geom::CubicBezier>(p0, p1, p2, p3))
+{
+ _name = "CanvasItemCurve:CubicBezier";
+ _pickable = false; // For now, nobody gets events from this class!
+
+ request_update();
+}
+
+/**
+ * Set a linear control curve. Points are in document coordinates.
+ */
+void CanvasItemCurve::set_coords(Geom::Point const &p0, Geom::Point const &p1)
+{
+ _name = "CanvasItemCurve:Line";
+ _curve = std::make_unique<Geom::LineSegment>(p0, p1);
+
+ request_update();
+}
+
+/**
+ * Set a cubic Bezier control curve. Points are in document coordinates.
+ */
+void CanvasItemCurve::set_coords(Geom::Point const &p0, Geom::Point const &p1, Geom::Point const &p2, Geom::Point const &p3)
+{
+ _name = "CanvasItemCurve:CubicBezier";
+ _curve = std::make_unique<Geom::CubicBezier>(p0, p1, p2, p3);
+
+ request_update();
+}
+
+/**
+ * Set stroke width.
+ */
+void CanvasItemCurve::set_width(int w)
+{
+ width = w;
+
+ request_update();
+}
+
+/**
+ * Set background stroke alpha.
+ */
+void CanvasItemCurve::set_bg_alpha(float alpha)
+{
+ bg_alpha = alpha;
+
+ request_update();
+}
+
+/**
+ * Returns distance between point in canvas units and nearest point on curve.
+ */
+double CanvasItemCurve::closest_distance_to(Geom::Point const &p)
+{
+ double d = Geom::infinity();
+ if (_curve) {
+ Geom::BezierCurve curve = *_curve;
+ curve *= _affine; // Document to canvas.
+ Geom::Point n = curve.pointAt(curve.nearestTime(p));
+ d = Geom::distance(p, n);
+ }
+ return d;
+}
+
+/**
+ * Returns true if point p (in canvas units) is within tolerance (canvas units) distance of curve.
+ */
+bool CanvasItemCurve::contains(Geom::Point const &p, double tolerance)
+{
+ return closest_distance_to(p) <= tolerance;
+}
+
+/**
+ * Update and redraw control curve.
+ */
+void CanvasItemCurve::update(Geom::Affine const &affine)
+{
+ if (_affine == affine && !_need_update) {
+ // Nothing to do.
+ return;
+ }
+
+ if (!_curve) {
+ return; // No curve! See node.h.
+ }
+
+ // Queue redraw of old area (erase previous content).
+ request_redraw(); // This is actually never useful as curves are always deleted
+ // and recreated when a node is moved! But keep it in case we
+ // change that. CHECK
+ // Get new bounds
+ _affine = affine;
+
+ // Trade off between updating a larger area (typically twice for Beziers?) vs computation time for bounds.
+ _bounds = _curve->boundsExact(); // Document units.
+ _bounds *= _affine; // Document to canvas.
+ _bounds.expandBy(2); // Room for stroke.
+
+ // Queue redraw of new area
+ request_redraw();
+
+ _need_update = false;
+}
+
+/**
+ * Render curve to screen via Cairo.
+ */
+void CanvasItemCurve::render(Inkscape::CanvasItemBuffer *buf)
+{
+ if (!buf) {
+ std::cerr << "CanvasItemCurve::Render: No buffer!" << std::endl;
+ return;
+ }
+
+ if (!_curve) {
+ // Curve not defined (see node.h).
+ return;
+ }
+
+ if (!_visible) {
+ // Hidden
+ return;
+ }
+
+ if (_curve->isDegenerate()) {
+ // Nothing to render!
+ return;
+ }
+
+ Geom::BezierCurve curve = *_curve;
+ curve *= _affine; // Document to canvas.
+ curve *= Geom::Translate(-buf->rect.min()); // Canvas to screen.
+
+ buf->cr->save();
+
+ buf->cr->begin_new_path();
+
+ if (curve.size() == 2) {
+ // Line
+ buf->cr->move_to(curve[0].x(), curve[0].y());
+ buf->cr->line_to(curve[1].x(), curve[1].y());
+ } else {
+ // Curve
+ buf->cr->move_to(curve[0].x(), curve[0].y());
+ buf->cr->curve_to(curve[1].x(), curve[1].y(), curve[2].x(), curve[2].y(), curve[3].x(), curve[3].y());
+ }
+
+ buf->cr->set_source_rgba(1.0, 1.0, 1.0, bg_alpha);
+ buf->cr->set_line_width(background_width);
+ buf->cr->stroke_preserve();
+
+ buf->cr->set_source_rgba(SP_RGBA32_R_F(_stroke), SP_RGBA32_G_F(_stroke),
+ SP_RGBA32_B_F(_stroke), SP_RGBA32_A_F(_stroke));
+ buf->cr->set_line_width(width);
+ buf->cr->stroke();
+
+ // Uncomment to show bounds
+ // Geom::Rect bounds = _bounds;
+ // bounds.expandBy(-1);
+ // bounds -= buf->rect.min();
+ // buf->cr->set_source_rgba(1.0, 0.0, 0.0, 1.0);
+ // buf->cr->rectangle(bounds.min().x(), bounds.min().y(), bounds.width(), bounds.height());
+ // buf->cr->stroke();
+
+ buf->cr->restore();
+}
+
+} // 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 :