From 33ed99902ed5ab36a45474ae7c281e49299dd6e9 Mon Sep 17 00:00:00 2001
From: Daniel Gibson <metalcaedes@gmail.com>
Date: Wed, 20 Mar 2024 15:22:21 +0100
Subject: [PATCH] Integrate ImGui into buildsystem, adjust its OpenGL code for
 qgl

---
 neo/CMakeLists.txt                            | 23 +++++++++--
 .../imgui/backends/imgui_impl_opengl2.cpp     | 41 +++++++++++++++++++
 2 files changed, 61 insertions(+), 3 deletions(-)

diff --git a/neo/CMakeLists.txt b/neo/CMakeLists.txt
index 12ecd2eb..ebcc23a3 100644
--- a/neo/CMakeLists.txt
+++ b/neo/CMakeLists.txt
@@ -739,6 +739,20 @@ set(src_idlib
 
 add_globbed_headers(src_idlib "idlib")
 
+set(src_imgui
+	libs/imgui/backends/imgui_impl_sdl2.cpp
+	libs/imgui/backends/imgui_impl_opengl2.cpp
+	
+	libs/imgui/imgui.cpp
+	libs/imgui/imgui_draw.cpp
+	libs/imgui/imgui_tables.cpp
+	libs/imgui/imgui_widgets.cpp
+	
+	libs/imgui/imgui_demo.cpp
+)
+
+add_globbed_headers(src_imgui "libs/imgui")
+
 set(src_game
 	game/AF.cpp
 	game/AFEntity.cpp
@@ -1148,6 +1162,7 @@ if(CORE)
 		${src_core}
 		${src_sys_base}
 		${src_sys_core}
+		${src_imgui}
 		${src_editor_tools}
 	)
 	
@@ -1156,7 +1171,9 @@ if(CORE)
 		set_property(DIRECTORY ${CMAKE_CURRENT_SOURCE_DIR} PROPERTY VS_STARTUP_PROJECT ${DHEWM3BINARY})
 	endif()
 
-	source_group(TREE ${CMAKE_CURRENT_SOURCE_DIR} PREFIX neo FILES ${src_core} ${src_sys_base} ${src_sys_core} ${src_editor_tools})
+	source_group(TREE ${CMAKE_CURRENT_SOURCE_DIR} PREFIX neo FILES ${src_core} ${src_sys_base} ${src_sys_core} ${src_imgui} ${src_editor_tools})
+
+	target_include_directories(${DHEWM3BINARY} PRIVATE "${CMAKE_SOURCE_DIR}/libs/imgui")
 
 if(HARDLINK_GAME)
 	set_target_properties(${DHEWM3BINARY} PROPERTIES COMPILE_DEFINITIONS "${TOOLS_DEFINES}")
@@ -1197,10 +1214,10 @@ if(DEDICATED)
 	source_group(TREE ${CMAKE_CURRENT_SOURCE_DIR} PREFIX neo FILES ${src_core} ${src_sys_base} ${src_stub_openal} ${src_stub_gl} ${src_debuggerServer})
 
 if(HARDLINK_GAME)
-	set_target_properties(${DHEWM3BINARY}ded PROPERTIES COMPILE_DEFINITIONS "ID_DEDICATED")
+	set_target_properties(${DHEWM3BINARY}ded PROPERTIES COMPILE_DEFINITIONS "IMGUI_DISABLE;ID_DEDICATED")
 	target_include_directories(${DHEWM3BINARY}ded PRIVATE ${game_includes})
 else()
-	set_target_properties(${DHEWM3BINARY}ded PROPERTIES COMPILE_DEFINITIONS "ID_DEDICATED;__DOOM_DLL__")
+	set_target_properties(${DHEWM3BINARY}ded PROPERTIES COMPILE_DEFINITIONS "IMGUI_DISABLE;ID_DEDICATED;__DOOM_DLL__")
 endif()
 	set_target_properties(${DHEWM3BINARY}ded PROPERTIES LINK_FLAGS "${ldflags}")
 	target_link_libraries(${DHEWM3BINARY}ded
diff --git a/neo/libs/imgui/backends/imgui_impl_opengl2.cpp b/neo/libs/imgui/backends/imgui_impl_opengl2.cpp
index 17935b1f..583f97ce 100644
--- a/neo/libs/imgui/backends/imgui_impl_opengl2.cpp
+++ b/neo/libs/imgui/backends/imgui_impl_opengl2.cpp
@@ -51,6 +51,9 @@
 #pragma clang diagnostic ignored "-Wnonportable-system-include-path"
 #endif
 
+// DG: use qgl instead of GL/gl.h for dhewm3 (where D3_OSTYPE is always defined by CMake)
+#ifndef D3_OSTYPE
+
 // Include OpenGL header (without an OpenGL loader) requires a bit of fiddling
 #if defined(_WIN32) && !defined(APIENTRY)
 #define APIENTRY __stdcall                  // It is customary to use APIENTRY for OpenGL function pointer declarations on all platforms.  Additionally, the Windows OpenGL header needs APIENTRY.
@@ -65,6 +68,44 @@
 #include <GL/gl.h>
 #endif
 
+#else // DG: use qgl
+
+#include "renderer/qgl.h"
+
+// creating some #defines for the used gl functions instead of adapting the code below
+// will make updating to new imgui versions easier
+#define glBindTexture         qglBindTexture
+#define glBlendFunc           qglBlendFunc
+#define glColorPointer        qglColorPointer
+#define glDeleteTextures      qglDeleteTextures
+#define glDisableClientState  qglDisableClientState
+#define glDisable             qglDisable
+#define glDrawElements        qglDrawElements
+#define glEnableClientState   qglEnableClientState
+#define glEnable              qglEnable
+#define glGenTextures         qglGenTextures
+#define glGetIntegerv         qglGetIntegerv
+#define glGetTexEnviv         qglGetTexEnviv
+#define glLoadIdentity        qglLoadIdentity
+#define glMatrixMode          qglMatrixMode
+#define glOrtho               qglOrtho
+#define glPixelStorei         qglPixelStorei
+#define glPolygonMode         qglPolygonMode
+#define glPopAttrib           qglPopAttrib
+#define glPopMatrix           qglPopMatrix
+#define glPushAttrib          qglPushAttrib
+#define glPushMatrix          qglPushMatrix
+#define glScissor             qglScissor
+#define glShadeModel          qglShadeModel
+#define glTexCoordPointer     qglTexCoordPointer
+#define glTexEnvi             qglTexEnvi
+#define glTexImage2D          qglTexImage2D
+#define glTexParameteri       qglTexParameteri
+#define glVertexPointer       qglVertexPointer
+#define glViewport            qglViewport
+
+#endif // DG: use qgl
+
 struct ImGui_ImplOpenGL2_Data
 {
     GLuint       FontTexture;