diff options
Diffstat (limited to 'examples/CMakeLists.txt')
| -rw-r--r-- | examples/CMakeLists.txt | 82 |
1 files changed, 64 insertions, 18 deletions
diff --git a/examples/CMakeLists.txt b/examples/CMakeLists.txt index 3e44d29fa..a8dfa970f 100644 --- a/examples/CMakeLists.txt +++ b/examples/CMakeLists.txt @@ -80,7 +80,7 @@ set(FLUID_SOURCES ) ############################################################ -# examples requiring fltk_images +# examples requiring fltk::images ############################################################ set(IMAGE_SOURCES @@ -100,7 +100,7 @@ set(CAIRO_SOURCES ) ############################################################ -# examples requiring OpenGL + libGLEW +# examples requiring OpenGL3 + GLEW ############################################################ set(OPENGL_SOURCES @@ -141,33 +141,79 @@ foreach(src ${CAIRO_SOURCES}) endforeach(src) ############################################################ -# create example programs with OpenGL + libGLEW +# create example programs with OpenGL3 + GLEW ############################################################ +# +# Note 1: macOS (Quartz) does not need GLEW, it's included in OpenGL +# Note 2: find_package(GLEW) finds either shared or static libs or both. +# Note 3: on Windows we set the variable GLEW_USE_STATIC_LIBS=TRUE because +# we *want* to find static libs but we *can* also use shared libs. +# Note 4: FindGLEW.cmake changed the library suffixes for MinGW in CMake 3.28.0, +# obviously "assuming" that ".lib" is Visual Studio only. There have been +# discussions about finding the "wrong" libraries since CMake 3.25 or so. +# Therefore the static lib "glew32s.lib" is not found if CMake 3.28 or +# higher is used (current version, as of this writing: 3.29.3). However, +# this assumption is probably not true for a pure C library (glew32s). +# This library *is* found and works well with CMake 3.15.0 - 3.27.9. +# Users may need to copy or rename "glew32s.lib" to "glew32s.a" +# if CMake 3.28 or higher is used. +# Albrecht-S, May 13, 2024 + +if(OPENGL_FOUND) + if(WIN32) + set(GLEW_USE_STATIC_LIBS TRUE) + endif() + set(_glew_lib GLEW::glew) + set(_glew_static FALSE) + if(APPLE AND NOT FLTK_BACKEND_X11) # macOS Quartz + set(_glew_lib) + set(GLEW_FOUND TRUE) + else() + # set(GLEW_VERBOSE TRUE) # make `find_package(GLEW)` verbose + set(_CMAKE_PREFIX_PATH_SAVED ${CMAKE_PREFIX_PATH}) + set(CMAKE_PREFIX_PATH ${FLTK_GLEW_DIR} ${CMAKE_PREFIX_PATH}) + find_package(GLEW MODULE) + set(CMAKE_PREFIX_PATH ${_CMAKE_PREFIX_PATH_SAVED}) + unset(_CMAKE_PREFIX_PATH_SAVED) + # Did we find the static lib? If yes, use it + if(TARGET GLEW::glew_s) + set(_glew_lib GLEW::glew_s) + set(_glew_static TRUE) + endif() + endif() -# Note: macOS does not need libGLEW + if(0) # Debug + fl_debug_var(OPENGL_FOUND) + fl_debug_var(GLEW_FOUND) + fl_debug_var(GLEW_DIR) + fl_debug_var(_glew_lib) + fl_debug_target(GLEW::glew) + fl_debug_target(GLEW::glew_s) + fl_debug_target(GLEW::GLEW) + endif() # /Debug -if(APPLE AND NOT FLTK_BACKEND_X11) - if(NOT LIB_GLEW) - set(LIB_GLEW TRUE) - endif() - set(REQUIRED_LIBS fltk::gl) -else() - set(REQUIRED_LIBS fltk::gl ${LIB_GLEW}) -endif() +endif(OPENGL_FOUND) + +if(OPENGL_FOUND AND (TARGET "${_glew_lib}" OR APPLE)) + + # GLEW was found, create the OpenGL3 targets: -if(OPENGL_FOUND AND LIB_GLEW) foreach(tgt ${OPENGL_SOURCES}) - fl_create_example(${tgt} ${tgt}.cxx "${REQUIRED_LIBS}") + fl_create_example(${tgt} ${tgt}.cxx "fltk::gl;${_glew_lib}") set_property(TARGET ${tgt} PROPERTY CXX_STANDARD 11) set_property(TARGET ${tgt} PROPERTY CXX_STANDARD_REQUIRED TRUE) + # define preprocessor macro GLEW_STATIC only if we link to the static lib + if(_glew_static) + target_compile_definitions(${tgt} PRIVATE "GLEW_STATIC") + endif() endforeach(tgt) else() + message(STATUS - "OpenGL or libGLEW not present: OpenGL example programs will not be built.") + "OpenGL or GLEW not present: OpenGL3 example programs will not be built.") fl_debug_var(OPENGL_FOUND) - fl_debug_var(LIB_GLEW) + fl_debug_var(GLEW_FOUND) message("") -endif(OPENGL_FOUND AND LIB_GLEW) -unset(REQUIRED_LIBS) +endif() # (OPENGL_FOUND AND TARGET "${_glew_lib}") |