Support OpenGL ES on *nix systems (#55)

* Support OpenGL ES on *nix systems

* support OpenGL ES on nix system (remove ES == mobile assumption)
  + add explicit options for both OGLES_GPGPU_OPENGL_ES{2,3}
    - these are mutually exclusive
    - if neither of the above is defined we use standard opengl (subset)
  + add OGLES_GPGPU_USE_EGL for EGL managed context (pass through to aglet)
* add generated header for OGLES_GPGPU_OPENGL_ES{2,3} version
  > w/ previous mobile == ES assumption this wasn't needed
  + update build with generated_file gl_definitions.h header to store defs
    > this wasn't needed in the exclusively mobile=es configuration
  + install generated gl_definitions.h header
  + introduce OGLES_GPGPU_NIX macro to indicate a nix variant
  + support includes of GLES2/gl2*.h, GLES3/gl3*.h, or GL/gl*.h headers as needed
  + update unit test to instantiate the correct context variant based on cmake options
* fix cmake logic in common_includes.h (android vs ios vs GL) for OGLES_GPGPU_OPENGL_ES{2,3} change
* video.h: use top level OGLES_GPGPU_TEXTURE_FORMAT, don't duplicate logic
* update aglet
  + bump version via URL + SHA1 in LOCAL config
  + translate OGLES_GPGPU_* -> AGLET_* options
* migrate test dependencies to unit test CMakeLists.txt
* update Hunter v0.23.151
* update HunterGate module
* bump version to v0.3.7

* update cmake package deps

* fix typo and cmake option location

* 's|ogesl_gpgpu|ogles_gpgpu'
* put required cmake options after project() and before hunter_add_package()

* fix opengl find_package() logic for *nix variants

* add include paths for mesa (test only) build

CMakeLists.txt

@@ -9,16 +9,34 @@ list(APPEND CMAKE_MODULE_PATH "${CMAKE_CURRENT_LIST_DIR}/cmake/modules")
 
 include("cmake/HunterGate.cmake")
 HunterGate(
-  URL "https://github.com/ruslo/hunter/archive/v0.22.13.tar.gz"
-  SHA1 "8b361d14d17c3526d41ecb62b6e905bdd9f3ee1d"
+  URL "https://github.com/ruslo/hunter/archive/v0.23.151.tar.gz"
+  SHA1 "68657b81508c2d3c248731b5a0c2125f19866721"
   LOCAL
-)
+  )
 
-project(ogles_gpgpu VERSION 0.3.6)
+project(ogles_gpgpu VERSION 0.3.7)
 
-hunter_add_package(check_ci_tag)
-find_package(check_ci_tag CONFIG REQUIRED)
-check_ci_tag()
+# !!! Make sure option OGLES_GPGPU_OPENG_ES3 occurs prior to the first
+# hunter_add_package() call.  This will allow us to modify settings
+# in dependencies appropriately (see cmake/Hunter/config.cmake)
+
+if(IOS OR ANDROID)
+  set(ogles_gpgpu_opengl_es2_dflt ON)
+  set(ogles_gpgpu_opengl_es3_dflt OFF)
+else()
+  set(ogles_gpgpu_opengl_es2_dflt OFF)
+  set(ogles_gpgpu_opengl_es3_dflt OFF)
+endif()
+
+option(OGLES_GPGPU_OPENGL_ES2 "Use OpenGL ES 2.0" ${ogles_gpgpu_opengl_es2_dflt})
+option(OGLES_GPGPU_OPENGL_ES3 "Use OpenGL ES 3.0" ${ogles_gpgpu_opengl_es3_dflt})
+option(OGLES_GPGPU_USE_EGL "Use EGL to manage the context (supports ES)" OFF)
+
+if(OGLES_GPGPU_OPENGL_ES2 AND OGLES_GPGPU_OPENGL_ES3)
+  message(FATAL_ERROR
+    "OGLES_GPGPU_OPENGL_ES2 and OGLES_GPGPU_OPENGL_ES3 are mutually exclusive"
+  )
+endif()
 
 set_property(GLOBAL PROPERTY USE_FOLDERS ON)
 
@@ -30,10 +48,9 @@ option(OGLES_GPGPU_VERBOSE "Perform per filter logging" OFF)
 option(OGLES_GPGPU_BUILD_TESTS "Build shader unit tests" OFF)
 option(OGLES_GPGPU_USE_OSMESA "Use MESA CPU OpenGL (via glfw)" OFF)
 
-# !!! Make sure option OGLES_GPGPU_OPENG_ES3 occurs prior to the first
-# hunter_add_package() call.  This will allow us to modify settings
-# in dependencies appropriately (see cmake/Hunter/config.cmake)
-option(OGLES_GPGPU_OPENGL_ES3 "Use OpenGL ES 3.0" OFF)
+hunter_add_package(check_ci_tag)
+find_package(check_ci_tag CONFIG REQUIRED)
+check_ci_tag()
 
 # See: cmake/Hunter/config.cmake
 hunter_add_package(sugar)
@@ -71,37 +88,11 @@ endif()
 # but they may only be run on platforms where an OpenGL context
 # is available
 if(OGLES_GPGPU_BUILD_TESTS)
-
   if(IOS AND DRISHTI_CI)
     # do not run test on CI (TODO: remote device testing)
   else()
     enable_testing()
   endif()
-
-  # Use GTest as unit test framework
-  hunter_add_package(GTest)
-  find_package(GTest CONFIG REQUIRED)
-  list(APPEND OGLES_GPGPU_TEST_LIBS GTest::gtest)
-
-  if(MSVC)
-    # TODO: Temporary aglet fix for appveyor?  Shouldn't be needed.
-    hunter_add_package(glew)
-    find_package(glew CONFIG REQUIRED)
-  endif()
-
-  # Use aglet for portable lightweight off screen opengl context
-  hunter_add_package(aglet)
-  find_package(aglet CONFIG REQUIRED)
-  list(APPEND OGLES_GPGPU_TEST_LIBS aglet::aglet)
-
-  # Use gauze for cross platform ctesting
-  hunter_add_package(gauze)
-  find_package(gauze CONFIG REQUIRED)
-  list(APPEND OGLES_GPGPU_TEST_LIBS gauze::gauze)
-
-  hunter_add_package(OpenCV)
-  find_package(OpenCV REQUIRED)
-  list(APPEND OGLES_GPGPU_TEST_LIBS "${OpenCV_LIBS}")
 endif()
 
 ## #################################################################

cmake/Config.cmake.in

@@ -24,7 +24,13 @@ elseif(@APPLE@)
     find_package(OpenGL REQUIRED)
   endif()
 else()
-  find_package(OpenGL REQUIRED)
+  if(@OGLES_GPGPU_OPENGL_ES2@)
+    find_package(gles2 REQUIRED)
+  elseif(@OGLES_GPGPU_OPENGL_ES3@)
+    find_package(gles3 REQUIRED)
+  else()
+    find_package(OpenGL REQUIRED)
+  endif()  
 endif()
 
 include("${CMAKE_CURRENT_LIST_DIR}/@targets_export_name@.cmake")

cmake/Hunter/config.cmake

@@ -17,16 +17,16 @@ if(OGLES_GPGPU_USE_OSMESA)
   hunter_config(glfw VERSION ${HUNTER_glfw_VERSION} CMAKE_ARGS GLFW_USE_OSMESA=ON)
 endif()
 
-# Note: Aglet is currently used to provide an OpenGL context for the unit tests
-# We need to make sure it is configured appropriately to provide one of:
-# * OpenGL ES 3.0 (or OpenGL 3.0)
-# * OpenGL ES 2.0
-# The context must be allocated approprately and we need to pull in the correct
-# set of headers with mixing them.
-if(OGLES_GPGPU_OPENGL_ES3)
-  set(aglet_es3 ON)
-else()
-  set(aglet_es3 OFF)
-endif()
+message("AGLET_OPENGL_ES3=${OGLES_GPGPU_OPENGL_ES3}")
+
+set(aglet_url "https://github.com/elucideye/aglet/archive/v1.3.3.tar.gz")
+set(aglet_sha1 432ad86638c30d221ad444ab73af214c2fe5a180)
+set(aglet_args
+  "AGLET_USE_EGL=${OGLES_GPGPU_USE_EGL}"
+  "AGLET_OPENGL_ES2=${OGLES_GPGPU_OPENGL_ES2}"
+  "AGLET_OPENGL_ES3=${OGLES_GPGPU_OPENGL_ES3}"
+)
+
+#hunter_config(aglet VERSION ${HUNTER_aglet_VERSION} CMAKE_ARGS AGLET_OPENGL_ES3=${aglet_es3})
+hunter_config(aglet URL ${aglet_url} SHA1 ${aglet_sha1} CMAKE_ARGS ${aglet_args})
 
-hunter_config(aglet VERSION ${HUNTER_aglet_VERSION} CMAKE_ARGS AGLET_OPENGL_ES3=${aglet_es3})