Fix OpenGL ES support

.gitignore

@@ -1,2 +1,3 @@
 build
 CMakeUserPresets.json
+.vs

CMakeLists.txt

@@ -58,8 +58,6 @@ if(NOT OpenGL_GL_PREFERENCE)
   set(OpenGL_GL_PREFERENCE "LEGACY")
 endif()
 
-find_package(OpenGL REQUIRED)
-
 include(GNUInstallDirs)
 
 # Define ImGui-SFML
@@ -72,7 +70,19 @@ target_include_directories(ImGui-SFML PUBLIC
 target_include_directories(ImGui-SFML SYSTEM PUBLIC
   $<BUILD_INTERFACE:${IMGUI_INCLUDE_DIR}>
 )
-target_link_libraries(ImGui-SFML PUBLIC SFML::Graphics OpenGL::GL)
+
+if(IOS)
+    target_link_libraries(ImGui-SFML PRIVATE "-framework OpenGLES")
+elseif(ANDROID)
+    find_package(EGL REQUIRED)
+    find_package(GLES REQUIRED)
+    target_link_libraries(ImGui-SFML PRIVATE EGL::EGL GLES::GLES)
+else()
+    find_package(OpenGL REQUIRED COMPONENTS OpenGL)
+    target_link_libraries(ImGui-SFML PRIVATE OpenGL::GL)
+endif()
+
+target_link_libraries(ImGui-SFML PUBLIC SFML::Graphics)
 if(WIN32 AND MINGW)
   target_link_libraries(ImGui-SFML PUBLIC imm32)
 endif()

cmake/FindEGL.cmake

@@ -0,0 +1,19 @@
+#
+# Try to find EGL library and include path.
+# Once done this will define
+#
+# EGL_FOUND
+# EGL_INCLUDE_PATH
+# EGL_LIBRARY
+#
+
+find_path(EGL_INCLUDE_DIR EGL/egl.h)
+find_library(EGL_LIBRARY NAMES EGL)
+
+include(FindPackageHandleStandardArgs)
+find_package_handle_standard_args(EGL DEFAULT_MSG EGL_LIBRARY EGL_INCLUDE_DIR)
+
+add_library(EGL::EGL IMPORTED UNKNOWN)
+set_target_properties(EGL::EGL PROPERTIES
+    INTERFACE_INCLUDE_DIRECTORIES ${EGL_INCLUDE_DIR}
+    IMPORTED_LOCATION ${EGL_LIBRARY})

cmake/FindGLES.cmake

@@ -0,0 +1,19 @@
+#
+# Try to find GLES library and include path.
+# Once done this will define
+#
+# GLES_FOUND
+# GLES_INCLUDE_PATH
+# GLES_LIBRARY
+#
+
+find_path(GLES_INCLUDE_DIR GLES/gl.h)
+find_library(GLES_LIBRARY NAMES GLESv1_CM)
+
+include(FindPackageHandleStandardArgs)
+find_package_handle_standard_args(GLES DEFAULT_MSG GLES_LIBRARY GLES_INCLUDE_DIR)
+
+add_library(GLES::GLES IMPORTED UNKNOWN)
+set_target_properties(GLES::GLES PROPERTIES
+    INTERFACE_INCLUDE_DIRECTORIES ${GLES_INCLUDE_DIR}
+    IMPORTED_LOCATION ${GLES_LIBRARY})

cmake/FindImGui.cmake

@@ -12,12 +12,19 @@ list(APPEND IMGUI_SEARCH_PATH
   ${IMGUI_DIR}
 )
 
+
+unset(IMGUI_INCLUDE_DIR)
+
 find_path(IMGUI_INCLUDE_DIR
   NAMES imgui.h
-  PATHS ${IMGUI_SEARCH_PATH}
+  HINTS ${IMGUI_SEARCH_PATH}
   NO_DEFAULT_PATH
+  NO_CMAKE_FIND_ROOT_PATH
 )
 
+file(GLOB MY_FILES "${IMGUI_DIR}/imgui.h")
+
+message(WARNING "Found: ${IMGUI_DIR} ${IMGUI_SEARCH_PATH} ${IMGUI_INCLUDE_DIR} ${MY_FILES}")
 if(NOT IMGUI_INCLUDE_DIR)
   message(FATAL_ERROR "IMGUI imgui.cpp not found. Set IMGUI_DIR to imgui's top-level path (containing \"imgui.cpp\" and \"imgui.h\" files).\n")
 endif()

imgui-SFML.cpp

@@ -911,7 +911,9 @@ void SetupRenderState(ImDrawData* draw_data, int fb_width, int fb_height)
     glEnableClientState(GL_COLOR_ARRAY);
     glDisableClientState(GL_NORMAL_ARRAY);
     glEnable(GL_TEXTURE_2D);
+#ifndef GL_VERSION_ES_CL_1_1
     glPolygonMode(GL_FRONT_AND_BACK, GL_FILL);
+#endif
     glShadeModel(GL_SMOOTH);
     glTexEnvi(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_MODULATE);
 
@@ -967,8 +969,12 @@ void RenderDrawLists(ImDrawData* draw_data)
     // Backup GL state
     GLint last_texture = 0;
     glGetIntegerv(GL_TEXTURE_BINDING_2D, &last_texture);
+
+#ifndef GL_VERSION_ES_CL_1_1
     GLint last_polygon_mode[2];
     glGetIntegerv(GL_POLYGON_MODE, last_polygon_mode);
+#endif
+
     GLint last_viewport[4];
     glGetIntegerv(GL_VIEWPORT, last_viewport);
     GLint last_scissor_box[4];
@@ -1060,9 +1066,13 @@ void RenderDrawLists(ImDrawData* draw_data)
     glPopMatrix();
     glMatrixMode(GL_PROJECTION);
     glPopMatrix();
+
+#ifndef GL_VERSION_ES_CL_1_1
     glPopAttrib();
     glPolygonMode(GL_FRONT, (GLenum)last_polygon_mode[0]);
     glPolygonMode(GL_BACK, (GLenum)last_polygon_mode[1]);
+#endif
+
     glViewport(last_viewport[0], last_viewport[1], (GLsizei)last_viewport[2], (GLsizei)last_viewport[3]);
     glScissor(last_scissor_box[0], last_scissor_box[1], (GLsizei)last_scissor_box[2], (GLsizei)last_scissor_box[3]);
     glShadeModel((GLenum)last_shade_model);