GPencil: New modules for Import and Export

This patch adds support to export and import grease pencil in several formats.

Inlude:

* Export SVG
* Export PDF (always from camera view)

* Import SVG

The import and export only support solid colors and not gradients or textures.

Requires libharu and pugixml.

For importing SVG, the NanoSVG lib is used, but this does not require installation (just a .h file embedded in the project  folder)

Example of PDF export: https://youtu.be/BMm0KeMJsI4

Reviewed By: #grease_pencil, HooglyBoogly

Maniphest Tasks: T83190, T79875, T83191, T83192

Differential Revision: https://developer.blender.org/D10482

1 files changed, 56 insertions, 0 deletions

diff --git a/source/blender/io/gpencil/intern/gpencil_io_import_svg.h b/source/blender/io/gpencil/intern/gpencil_io_import_svg.h
new file mode 100644
index 00000000000..6a34ec8423b
--- /dev/null
+++ b/source/blender/io/gpencil/intern/gpencil_io_import_svg.h
@@ -0,0 +1,56 @@
+/*
+ * 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, write to the Free Software Foundation,
+ * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ *
+ * The Original Code is Copyright (C) 2020 Blender Foundation
+ * All rights reserved.
+ */
+#pragma once
+
+/** \file
+ * \ingroup bgpencil
+ */
+#include "gpencil_io_import_base.h"
+
+struct GpencilIOParams;
+struct NSVGshape;
+struct NSVGpath;
+struct bGPdata;
+struct bGPDframe;
+
+#define SVG_IMPORTER_NAME "SVG Import for Grease Pencil"
+#define SVG_IMPORTER_VERSION "v1.0"
+
+namespace blender::io::gpencil {
+
+class GpencilImporterSVG : public GpencilImporter {
+
+ public:
+  GpencilImporterSVG(const char *filename, const struct GpencilIOParams *iparams);
+
+  bool read();
+
+ protected:
+ private:
+  void create_stroke(struct bGPdata *gpd_,
+                     struct bGPDframe *gpf,
+                     struct NSVGshape *shape,
+                     struct NSVGpath *path,
+                     const int32_t mat_index,
+                     const float matrix[4][4]);
+
+  void convert_color(const int32_t color, float r_linear_rgba[4]);
+};
+
+}  // namespace blender::io::gpencil