Add rendering script for logo with margins e.g. for the chat avatar

Variants of the logo inlcuding specific margins can be generated.
That is needed if the logo is used without the possibility to dynamically
adjust its margins.

.gitignore

@@ -7,3 +7,4 @@ CMakeLists.txt.*
 build*
 .kdev4/
 *.kdev4
+support-chat-avatar.png

utils/render-graphics.sh

@@ -0,0 +1,39 @@
+#!/bin/bash
+
+# SPDX-FileCopyrightText: 2023 Melvin Keskin <melvo@olomono.de>
+#
+# SPDX-License-Identifier: GPL-3.0-or-later
+
+QXMPP_SOURCES=$(dirname "$(readlink -f "${0}")")/..
+
+echo "*****************************************"
+echo "Rendering graphics"
+echo "*****************************************"
+
+render_support_chat_avatar() {
+    render_svg_with_margin $QXMPP_SOURCES/logo.svg $QXMPP_SOURCES/support-chat-avatar.png 300 300 18
+}
+
+# $1 - $4: see render_svg()
+# $5: margin
+render_svg_with_margin() {
+    output_directory=$(dirname $2)
+    mkdir -p $output_directory
+    tmp_file=$output_directory/rendered_tmp.svg
+    inkscape -o $tmp_file --export-margin=$5 $1
+    render_svg $tmp_file $2 $3 $4
+    rm $tmp_file
+}
+
+# $1: input file
+# $2: output file
+# $3: width
+# $4: height
+render_svg() {
+    inkscape -o $2 -w $3 -h $4 $1 >/dev/null
+    optipng -quiet -o7 $2 >/dev/null
+    advpng -z4 $2 >/dev/null
+    echo "Created "$2
+}
+
+render_support_chat_avatar