Build docs (#49)

* add CMake files for building the documentation
* dynamically generate PNG files from SGVs
* add workflow for building the documentation
* rename original opengx PDF file. This is to make it clear that it's from 2012.

.github/workflows/docs.yml

@@ -0,0 +1,37 @@
+name: Documentation
+
+on:
+ push:
+ paths:
+ - 'doc/**'
+ pull_request:
+ paths:
+ - 'doc/**'
+
+jobs:
+ docs:
+ name: ubuntu-latest
+ runs-on: ubuntu-latest
+
+ steps:
+ - uses: actions/checkout@v4
+
+ - name: Install dependencies
+ run: |
+ sudo apt update
+ sudo apt install -y \
+ cmake \
+ imagemagick \
+ texlive-latex-extra
+
+ - name: Build
+ run: |
+ cmake -S. -Bbuild -DBUILD_DOCS=ON -DBUILD_OPENGX=OFF
+ cd build
+ make 
+
+ - name: Archive built documentation
+ uses: actions/upload-artifact@v4
+ with:
+ name: opengx.pdf
+ path: build/doc/src/opengx.pdf

CMakeLists.txt

@@ -1,9 +1,18 @@
 cmake_minimum_required(VERSION 3.13)
 project(OpenGX VERSION 0.1)
 
+option(BUILD_OPENGX "Build the opengx library" ON)
+option(BUILD_DOCS "Build the documentation" OFF)
+
 set(CMAKE_C_STANDARD 11)
 set(CMAKE_CXX_STANDARD 17)
 
+set(CMAKE_MODULE_PATH "${CMAKE_SOURCE_DIR}/cmake" "${CMAKE_MODULE_PATH}")
+
+# This is ON by default, of course, but we allow switching it off in case one
+# just needs to build the documentation
+if(BUILD_OPENGX)
+
 set(TARGET opengx)
 
 include(GNUInstallDirs)
@@ -43,3 +52,10 @@ install(FILES ${CMAKE_CURRENT_BINARY_DIR}/opengl.pc
  DESTINATION "${CMAKE_INSTALL_LIBDIR}/pkgconfig")
 install(FILES OpenGLConfig.cmake
  DESTINATION "${CMAKE_INSTALL_LIBDIR}/cmake/OpenGL")
+
+endif(BUILD_OPENGX)
+
+if(BUILD_DOCS)
+ include(UseLATEX)
+ add_subdirectory(doc/src)
+endif()