glew fix

Former-commit-id: 5d4e0e7fb9e1b9e8d1e9a64857fe38899d45c01b

include/igl/viewer/OpenGL_shader.cpp

@@ -8,21 +8,6 @@
 
 #include "OpenGL_shader.h"
 
-#ifndef __APPLE__
-#  define GLEW_STATIC
-#  include <GL/glew.h>
-#endif
-
-#ifdef __APPLE__
-#   include <OpenGL/gl3.h>
-#   define __gl_h_ /* Prevent inclusion of the old gl.h */
-#else
-#   ifdef _WIN32
-#       include <windows.h>
-#   endif
-#   include <GL/gl.h>
-#endif
-
 #include <iostream>
 #include <fstream>
 

shared/cmake/CMakeLists.txt

@@ -139,7 +139,6 @@ if(LIBIGL_WITH_EMBREE)
   if(LIBIGL_USE_STATIC_LIBRARY)
     CompileIGL_Module("embree")
     target_include_directories(iglembree PRIVATE ${EMBREE_DIR}/include)
-    target_compile_options(iglembree PRIVATE -Wno-deprecated-declarations) # avoid some warnings during embree compilation
   endif()
 endif()
 
@@ -224,10 +223,10 @@ if(LIBIGL_WITH_VIEWER)
 
   ### GLEW for linux and windows
   if(UNIX OR (WIN32 AND NOT LIBIGL_WITH_NANOGUI)) ### Compile glew if needed
-    add_library(glew STATIC "${NANOGUI_DIR}/ext/glew/src/glew.c")
-    target_include_directories(glew PRIVATE "${NANOGUI_DIR}/ext/glew/include")
+    set(GLEW_INSTALL OFF CACHE BOOL " " FORCE)
+    add_subdirectory("${NANOGUI_DIR}/ext/glew" "glew")
   endif()
-  if(UNIX OR WIN32)
+  if(NOT APPLE)
     list(APPEND VIEWER_INCLUDE_DIRS "${NANOGUI_DIR}/ext/glew/include")
     list(APPEND VIEWER_LIBRARIES "glew")
   endif()
@@ -254,11 +253,13 @@ if(LIBIGL_WITH_OPENGL_AND_PNG)
   if(LIBIGL_USE_STATIC_LIBRARY)
     CompileIGL_Module("opengl")
     CompileIGL_Module("opengl2")
+    CompileIGL_Module("png")
+    target_include_directories(iglpng PRIVATE ${STB_IMAGE_DIR})
     if(NOT APPLE)
+      target_include_directories(iglopengl PRIVATE "${LIBIGL_EXTERNAL}/nanogui/ext/glew/include")
       target_include_directories(iglopengl2 PRIVATE "${LIBIGL_EXTERNAL}/nanogui/ext/glew/include")
+      target_include_directories(iglpng PRIVATE "${LIBIGL_EXTERNAL}/nanogui/ext/glew/include")
     endif()
-    CompileIGL_Module("png")
-    target_include_directories(iglpng PRIVATE ${STB_IMAGE_DIR})
   endif()
 endif()