Add support for key press and release events.

Makefile

@@ -1,4 +1,24 @@
-SOURCES = cpp/opengl/render_context_glx.cpp cpp/opengl/render_opengles.cpp cpp/math.cpp
+# Copyright (C) 2022 RozK
+#
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU Affero General Public License as published by
+# the Free Software Foundation, either version 3 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 Affero General Public License for more details.
+#
+# You should have received a copy of the GNU Affero General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+SOURCES = \
+cpp/opengl/render_context_glx.cpp \
+cpp/opengl/render_opengles.cpp \
+cpp/events/events_x11.cpp \
+cpp/math.cpp
+
 OUTPUTFILE = engine.so
 
 CXXFLAGS = -fpic -Wall -Werror -O2 -flto -fomit-frame-pointer -ffast-math -funroll-loops -fno-rtti -fno-exceptions