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-rw-r--r--src/object/viewbox.cpp328
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diff --git a/src/object/viewbox.cpp b/src/object/viewbox.cpp
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+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * viewBox helper class, common code used by root, symbol, marker, pattern, image, view
+ *
+ * Authors:
+ * Lauris Kaplinski <lauris@kaplinski.com> (code extracted from symbol.cpp)
+ * Tavmjong Bah <tavmjong@free.fr>
+ * Johan Engelen
+ *
+ * Copyright (C) 2013-2014 Tavmjong Bah, authors
+ *
+ * Released under GNU GPL v2+, read the file 'COPYING' for more information.
+ *
+ */
+
+#include <2geom/transforms.h>
+
+#include "viewbox.h"
+#include "enums.h"
+#include "sp-item.h"
+#include "svg/stringstream.h"
+
+#include <map>
+
+namespace {
+std::map<unsigned int, char const *> const ASPECT_ALIGN_STRINGS{
+ {SP_ASPECT_NONE, "none"}, //
+ {SP_ASPECT_XMIN_YMIN, "xMinYMin"}, //
+ {SP_ASPECT_XMID_YMIN, "xMidYMin"}, //
+ {SP_ASPECT_XMAX_YMIN, "xMaxYMin"}, //
+ {SP_ASPECT_XMIN_YMID, "xMinYMid"}, //
+ {SP_ASPECT_XMID_YMID, "xMidYMid"}, //
+ {SP_ASPECT_XMAX_YMID, "xMaxYMid"}, //
+ {SP_ASPECT_XMIN_YMAX, "xMinYMax"}, //
+ {SP_ASPECT_XMID_YMAX, "xMidYMax"}, //
+ {SP_ASPECT_XMAX_YMAX, "xMaxYMax"}, //
+};
+}
+
+SPViewBox::SPViewBox()
+ : viewBox_set(false)
+ , viewBox()
+ , aspect_set(false)
+ , aspect_align(SP_ASPECT_XMID_YMID) // Default per spec
+ , aspect_clip(SP_ASPECT_MEET)
+ , c2p(Geom::identity())
+{
+}
+
+void SPViewBox::set_viewBox(const gchar* value) {
+
+ if (value) {
+ gchar *eptr = const_cast<gchar*>(value); // const-cast necessary because of const-incorrect interface definition of g_ascii_strtod
+
+ double x = g_ascii_strtod (eptr, &eptr);
+
+ while (*eptr && ((*eptr == ',') || (*eptr == ' '))) {
+ eptr++;
+ }
+
+ double y = g_ascii_strtod (eptr, &eptr);
+
+ while (*eptr && ((*eptr == ',') || (*eptr == ' '))) {
+ eptr++;
+ }
+
+ double width = g_ascii_strtod (eptr, &eptr);
+
+ while (*eptr && ((*eptr == ',') || (*eptr == ' '))) {
+ eptr++;
+ }
+
+ double height = g_ascii_strtod (eptr, &eptr);
+
+ while (*eptr && ((*eptr == ',') || (*eptr == ' '))) {
+ eptr++;
+ }
+
+ if ((width > 0) && (height > 0)) {
+ /* Set viewbox */
+ this->viewBox = Geom::Rect::from_xywh(x, y, width, height);
+ this->viewBox_set = true;
+ } else {
+ this->viewBox_set = false;
+ }
+ } else {
+ this->viewBox_set = false;
+ }
+
+ // The C++ way? -- not necessarily using iostreams
+ // std::string sv( value );
+ // std::replace( sv.begin(), sv.end(), ',', ' ');
+ // std::stringstream ss( sv );
+ // double x, y, width, height;
+ // ss >> x >> y >> width >> height;
+}
+
+void SPViewBox::set_preserveAspectRatio(const gchar* value) {
+
+ /* Do setup before, so we can use break to escape */
+ this->aspect_set = false;
+ this->aspect_align = SP_ASPECT_XMID_YMID; // Default per spec
+ this->aspect_clip = SP_ASPECT_MEET;
+
+ if (value) {
+ const gchar *p = value;
+
+ while (*p && (*p == 32)) {
+ p += 1;
+ }
+
+ if (!*p) {
+ return;
+ }
+
+ const gchar *e = p;
+
+ while (*e && (*e != 32)) {
+ e += 1;
+ }
+
+ int len = e - p;
+
+ if (len > 8) { // Can't have buffer overflow as 8 < 256
+ return;
+ }
+
+ gchar c[256];
+ memcpy (c, value, len);
+
+ c[len] = 0;
+
+ /* Now the actual part */
+ unsigned int align = SP_ASPECT_NONE;
+ if (!strcmp (c, "none")) {
+ align = SP_ASPECT_NONE;
+ } else if (!strcmp (c, "xMinYMin")) {
+ align = SP_ASPECT_XMIN_YMIN;
+ } else if (!strcmp (c, "xMidYMin")) {
+ align = SP_ASPECT_XMID_YMIN;
+ } else if (!strcmp (c, "xMaxYMin")) {
+ align = SP_ASPECT_XMAX_YMIN;
+ } else if (!strcmp (c, "xMinYMid")) {
+ align = SP_ASPECT_XMIN_YMID;
+ } else if (!strcmp (c, "xMidYMid")) {
+ align = SP_ASPECT_XMID_YMID;
+ } else if (!strcmp (c, "xMaxYMid")) {
+ align = SP_ASPECT_XMAX_YMID;
+ } else if (!strcmp (c, "xMinYMax")) {
+ align = SP_ASPECT_XMIN_YMAX;
+ } else if (!strcmp (c, "xMidYMax")) {
+ align = SP_ASPECT_XMID_YMAX;
+ } else if (!strcmp (c, "xMaxYMax")) {
+ align = SP_ASPECT_XMAX_YMAX;
+ } else {
+ return;
+ }
+
+ unsigned int clip = SP_ASPECT_MEET;
+
+ while (*e && (*e == 32)) {
+ e += 1;
+ }
+
+ if (*e) {
+ if (!strcmp (e, "meet")) {
+ clip = SP_ASPECT_MEET;
+ } else if (!strcmp (e, "slice")) {
+ clip = SP_ASPECT_SLICE;
+ } else {
+ return;
+ }
+ }
+
+ this->aspect_set = true;
+ this->aspect_align = align;
+ this->aspect_clip = clip;
+ }
+}
+
+// Apply scaling from viewbox
+void SPViewBox::apply_viewbox(const Geom::Rect& in, double scale_none) {
+
+ /* Determine actual viewbox in viewport coordinates */
+ // scale_none is the scale that would apply if the viewbox and page size are same size
+ // it is passed here because it is a double-precision variable, while 'in' is originally float
+ double x = 0.0;
+ double y = 0.0;
+ double scale_x = in.width() / this->viewBox.width();
+ double scale_y = in.height() / this->viewBox.height();
+ double scale_uniform = 1.0; // used only if scaling is uniform
+
+ if (Geom::are_near(scale_x / scale_y, 1.0, Geom::EPSILON)) {
+ // scaling is already uniform, reduce numerical error
+ scale_uniform = (scale_x + scale_y)/2.0;
+ if (Geom::are_near(scale_uniform / scale_none, 1.0, Geom::EPSILON))
+ scale_uniform = scale_none; // objects are same size, reduce numerical error
+ scale_x = scale_uniform;
+ scale_y = scale_uniform;
+ } else if (this->aspect_align != SP_ASPECT_NONE) {
+ // scaling is not uniform, but force it to be
+ scale_uniform = (this->aspect_clip == SP_ASPECT_MEET) ? MIN (scale_x, scale_y) : MAX (scale_x, scale_y);
+ scale_x = scale_uniform;
+ scale_y = scale_uniform;
+ double width = this->viewBox.width() * scale_uniform;
+ double height = this->viewBox.height() * scale_uniform;
+
+ /* Now place viewbox to requested position */
+ switch (this->aspect_align) {
+ case SP_ASPECT_XMIN_YMIN:
+ break;
+ case SP_ASPECT_XMID_YMIN:
+ x = 0.5 * (in.width() - width);
+ break;
+ case SP_ASPECT_XMAX_YMIN:
+ x = 1.0 * (in.width() - width);
+ break;
+ case SP_ASPECT_XMIN_YMID:
+ y = 0.5 * (in.height() - height);
+ break;
+ case SP_ASPECT_XMID_YMID:
+ x = 0.5 * (in.width() - width);
+ y = 0.5 * (in.height() - height);
+ break;
+ case SP_ASPECT_XMAX_YMID:
+ x = 1.0 * (in.width() - width);
+ y = 0.5 * (in.height() - height);
+ break;
+ case SP_ASPECT_XMIN_YMAX:
+ y = 1.0 * (in.height() - height);
+ break;
+ case SP_ASPECT_XMID_YMAX:
+ x = 0.5 * (in.width() - width);
+ y = 1.0 * (in.height() - height);
+ break;
+ case SP_ASPECT_XMAX_YMAX:
+ x = 1.0 * (in.width() - width);
+ y = 1.0 * (in.height() - height);
+ break;
+ default:
+ break;
+ }
+ }
+
+ /* Viewbox transform from scale and position */
+ Geom::Affine q;
+ q[0] = scale_x;
+ q[1] = 0.0;
+ q[2] = 0.0;
+ q[3] = scale_y;
+ q[4] = x - scale_x * this->viewBox.left();
+ q[5] = y - scale_y * this->viewBox.top();
+
+ // std::cout << " q\n" << q << std::endl;
+
+ /* Append viewbox transformation */
+ this->c2p = q * this->c2p;
+}
+
+SPItemCtx SPViewBox::get_rctx(const SPItemCtx* ictx, double scale_none) {
+
+ /* Create copy of item context */
+ SPItemCtx rctx = *ictx;
+
+ /* Calculate child to parent transformation */
+ /* Apply parent translation (set up as viewport) */
+ this->c2p = Geom::Translate(rctx.viewport.min());
+
+ if (this->viewBox_set) {
+ // Adjusts c2p for viewbox
+ apply_viewbox( rctx.viewport, scale_none );
+ }
+
+ rctx.i2doc = this->c2p * rctx.i2doc;
+
+ /* If viewBox is set initialize child viewport */
+ /* Otherwise it is already correct */
+ if (this->viewBox_set) {
+ rctx.viewport = this->viewBox;
+ rctx.i2vp = Geom::identity();
+ }
+
+ return rctx;
+}
+
+/**
+ * Write viewBox attribute to XML, if set.
+ */
+void SPViewBox::write_viewBox(Inkscape::XML::Node *repr) const
+{
+ if (viewBox_set) {
+ Inkscape::SVGOStringStream os;
+ os << viewBox.left() << " " //
+ << viewBox.top() << " " //
+ << viewBox.width() << " " //
+ << viewBox.height();
+
+ repr->setAttribute("viewBox", os.str());
+ }
+}
+
+/**
+ * Write preserveAspectRatio attribute to XML, if set.
+ */
+void SPViewBox::write_preserveAspectRatio(Inkscape::XML::Node *repr) const
+{
+ if (aspect_set) {
+ std::string aspect = ASPECT_ALIGN_STRINGS.at(aspect_align);
+
+ if (aspect_clip == SP_ASPECT_SLICE) {
+ aspect += " slice";
+ }
+
+ repr->setAttribute("preserveAspectRatio", aspect);
+ }
+}
+
+/*
+ Local Variables:
+ mode:c++
+ c-file-style:"stroustrup"
+ c-basic-offset:2
+ c-file-offsets:((innamespace . 0)(inline-open . 0)(case-label . +))
+ indent-tabs-mode:nil
+ fill-column:99
+ End:
+*/
+// vim: filetype=cpp:expandtab:shiftwidth=2:tabstop=8:softtabstop=2:fileencoding=utf-8:textwidth=99 :
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