1 files changed, 142 insertions, 0 deletions
diff --git a/src/object/sp-linear-gradient.cpp b/src/object/sp-linear-gradient.cpp
new file mode 100644
index 0000000..a6130a2
--- /dev/null
+++ b/src/object/sp-linear-gradient.cpp
@@ -0,0 +1,142 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/** @file
+ * TODO: insert short description here
+ *//*
+ * Authors: see git history
+ *
+ * Copyright (C) 2018 Authors
+ * Released under GNU GPL v2+, read the file 'COPYING' for more information.
+ */
+#include <cairo.h>
+
+#include "sp-linear-gradient.h"
+
+#include "attributes.h"
+#include "style.h"
+#include "xml/repr.h"
+
+/*
+ * Linear Gradient
+ */
+SPLinearGradient::SPLinearGradient() : SPGradient() {
+    this->x1.unset(SVGLength::PERCENT, 0.0, 0.0);
+    this->y1.unset(SVGLength::PERCENT, 0.0, 0.0);
+    this->x2.unset(SVGLength::PERCENT, 1.0, 1.0);
+    this->y2.unset(SVGLength::PERCENT, 0.0, 0.0);
+}
+
+SPLinearGradient::~SPLinearGradient() = default;
+
+void SPLinearGradient::build(SPDocument *document, Inkscape::XML::Node *repr) {
+    this->readAttr(SPAttr::X1);
+    this->readAttr(SPAttr::Y1);
+    this->readAttr(SPAttr::X2);
+    this->readAttr(SPAttr::Y2);
+
+    SPGradient::build(document, repr);
+}
+
+/**
+ * Callback: set attribute.
+ */
+void SPLinearGradient::set(SPAttr key, const gchar* value) {
+    switch (key) {
+        case SPAttr::X1:
+            this->x1.readOrUnset(value, SVGLength::PERCENT, 0.0, 0.0);
+            this->requestModified(SP_OBJECT_MODIFIED_FLAG);
+            break;
+
+        case SPAttr::Y1:
+            this->y1.readOrUnset(value, SVGLength::PERCENT, 0.0, 0.0);
+            this->requestModified(SP_OBJECT_MODIFIED_FLAG);
+            break;
+
+        case SPAttr::X2:
+            this->x2.readOrUnset(value, SVGLength::PERCENT, 1.0, 1.0);
+            this->requestModified(SP_OBJECT_MODIFIED_FLAG);
+            break;
+
+        case SPAttr::Y2:
+            this->y2.readOrUnset(value, SVGLength::PERCENT, 0.0, 0.0);
+            this->requestModified(SP_OBJECT_MODIFIED_FLAG);
+            break;
+
+        default:
+            SPGradient::set(key, value);
+            break;
+    }
+}
+
+void
+SPLinearGradient::update(SPCtx *ctx, guint flags)
+{
+    // To do: Verify flags.
+    if (flags & (SP_OBJECT_MODIFIED_FLAG | SP_OBJECT_STYLE_MODIFIED_FLAG | SP_OBJECT_VIEWPORT_MODIFIED_FLAG)) {
+
+        SPItemCtx const *ictx = reinterpret_cast<SPItemCtx const *>(ctx);
+
+        if (getUnits() == SP_GRADIENT_UNITS_USERSPACEONUSE) {
+            double w = ictx->viewport.width();
+            double h = ictx->viewport.height();
+            double const em = style->font_size.computed;
+            double const ex = 0.5 * em;  // fixme: get x height from pango or libnrtype.
+
+            this->x1.update(em, ex, w);
+            this->y1.update(em, ex, h);
+            this->x2.update(em, ex, w);
+            this->y2.update(em, ex, h);
+        }
+    }
+}
+
+/**
+ * Callback: write attributes to associated repr.
+ */
+Inkscape::XML::Node* SPLinearGradient::write(Inkscape::XML::Document *xml_doc, Inkscape::XML::Node *repr, guint flags) {
+    if ((flags & SP_OBJECT_WRITE_BUILD) && !repr) {
+        repr = xml_doc->createElement("svg:linearGradient");
+    }
+
+    if ((flags & SP_OBJECT_WRITE_ALL) || this->x1._set) {
+        repr->setAttributeSvgDouble("x1", this->x1.computed);
+    }
+
+    if ((flags & SP_OBJECT_WRITE_ALL) || this->y1._set) {
+        repr->setAttributeSvgDouble("y1", this->y1.computed);
+    }
+
+    if ((flags & SP_OBJECT_WRITE_ALL) || this->x2._set) {
+        repr->setAttributeSvgDouble("x2", this->x2.computed);
+    }
+
+    if ((flags & SP_OBJECT_WRITE_ALL) || this->y2._set) {
+        repr->setAttributeSvgDouble("y2", this->y2.computed);
+    }
+
+    SPGradient::write(xml_doc, repr, flags);
+
+    return repr;
+}
+
+cairo_pattern_t* SPLinearGradient::pattern_new(cairo_t * /*ct*/, Geom::OptRect const &bbox, double opacity) {
+    this->ensureVector();
+
+    cairo_pattern_t *cp = cairo_pattern_create_linear(
+        this->x1.computed, this->y1.computed,
+        this->x2.computed, this->y2.computed);
+
+    sp_gradient_pattern_common_setup(cp, this, bbox, opacity);
+
+    return cp;
+}
+
+/*
+  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 :