cmake HAVE_PNG examples

Kitware/VTK ThirdParty/gl2ps/vtkgl2ps/CMakeLists.txt :22 

target_compile_definitions(gl2ps
  PRIVATE
    HAVE_ZLIB
    HAVE_PNG)

SRB2-Mobile/SRB2-Android src/CMakeLists.txt :184 

target_compile_definitions(SRB2SDL2 PRIVATE -DHAVE_ZLIB -DHAVE_PNG -DHAVE_CURL -D_LARGEFILE64_SOURCE)

fukuchi/libqrencode CMakeLists.txt :141 

add_definitions(-DHAVE_PNG=1)