From 1509842107dcded1a596ae1c24e7d74300c65555 Mon Sep 17 00:00:00 2001
From: ocornut <omarcornut@gmail.com>
Date: Wed, 24 Jan 2024 15:15:15 +0100
Subject: [PATCH] Backends: OpenGL3: Shallow tweak of compile-time extensions
 detection.

Detect polygon mode using same method as others (not define/symbol).
IMGUI_IMPL_OPENGL_MAY_HAVE_EXTENSIONS -> IMGUI_IMPL_OPENGL_HAS_EXTENSIONS
---
 backends/imgui_impl_glfw.cpp    |  4 +---
 backends/imgui_impl_opengl3.cpp | 42 +++++++++++++++------------------
 2 files changed, 20 insertions(+), 26 deletions(-)

diff --git a/backends/imgui_impl_glfw.cpp b/backends/imgui_impl_glfw.cpp
index b49c99bb..a968fe30 100644
--- a/backends/imgui_impl_glfw.cpp
+++ b/backends/imgui_impl_glfw.cpp
@@ -114,7 +114,7 @@ enum GlfwClientApi
 {
     GlfwClientApi_Unknown,
     GlfwClientApi_OpenGL,
-    GlfwClientApi_Vulkan
+    GlfwClientApi_Vulkan,
 };
 
 struct ImGui_ImplGlfw_Data
@@ -674,11 +674,9 @@ static void ImGui_ImplGlfw_UpdateMouseData()
     ImGui_ImplGlfw_Data* bd = ImGui_ImplGlfw_GetBackendData();
     ImGuiIO& io = ImGui::GetIO();
 
-
     // (those braces are here to reduce diff with multi-viewports support in 'docking' branch)
     {
         GLFWwindow* window = bd->Window;
-
 #ifdef __EMSCRIPTEN__
         const bool is_window_focused = true;
 #else
diff --git a/backends/imgui_impl_opengl3.cpp b/backends/imgui_impl_opengl3.cpp
index 1c63641a..b3a510bc 100644
--- a/backends/imgui_impl_opengl3.cpp
+++ b/backends/imgui_impl_opengl3.cpp
@@ -176,9 +176,20 @@
 #define GL_VERTEX_ARRAY_BINDING GL_VERTEX_ARRAY_BINDING_OES
 #endif
 
-// Desktop GL 2.0+ has glPolygonMode() which GL ES and WebGL don't have.
-#ifdef GL_POLYGON_MODE
-#define IMGUI_IMPL_HAS_POLYGON_MODE
+// Desktop GL 2.0+ has extension and glPolygonMode() which GL ES and WebGL don't have..
+#if !defined(IMGUI_IMPL_OPENGL_ES2) && !defined(IMGUI_IMPL_OPENGL_ES3)
+#define IMGUI_IMPL_OPENGL_HAS_EXTENSIONS        // has glGetIntegerv(GL_NUM_EXTENSIONS)
+#define IMGUI_IMPL_OPENGL_HAS_POLYGON_MODE      // has glPolygonMode()
+#endif
+
+// Desktop GL 2.1+ and GL ES 3.0+ have glBindBuffer() with GL_PIXEL_UNPACK_BUFFER target.
+#if !defined(IMGUI_IMPL_OPENGL_ES2)
+#define IMGUI_IMPL_OPENGL_MAY_HAVE_BIND_BUFFER_PIXEL_UNPACK
+#endif
+
+// Desktop GL 3.1+ has GL_PRIMITIVE_RESTART state
+#if !defined(IMGUI_IMPL_OPENGL_ES2) && !defined(IMGUI_IMPL_OPENGL_ES3) && defined(GL_VERSION_3_1)
+#define IMGUI_IMPL_OPENGL_MAY_HAVE_PRIMITIVE_RESTART
 #endif
 
 // Desktop GL 3.2+ has glDrawElementsBaseVertex() which GL ES and WebGL don't have.
@@ -191,21 +202,6 @@
 #define IMGUI_IMPL_OPENGL_MAY_HAVE_BIND_SAMPLER
 #endif
 
-// Desktop GL and GL ES 3.0+ have glBindBuffer() with GL_PIXEL_UNPACK_BUFFER target.
-#if !defined(IMGUI_IMPL_OPENGL_ES2)
-#define IMGUI_IMPL_OPENGL_MAY_HAVE_BIND_BUFFER_PIXEL_UNPACK
-#endif
-
-// Desktop GL 3.1+ has GL_PRIMITIVE_RESTART state
-#if !defined(IMGUI_IMPL_OPENGL_ES2) && !defined(IMGUI_IMPL_OPENGL_ES3) && defined(GL_VERSION_3_1)
-#define IMGUI_IMPL_OPENGL_MAY_HAVE_PRIMITIVE_RESTART
-#endif
-
-// Desktop GL use extension detection
-#if !defined(IMGUI_IMPL_OPENGL_ES2) && !defined(IMGUI_IMPL_OPENGL_ES3)
-#define IMGUI_IMPL_OPENGL_MAY_HAVE_EXTENSIONS
-#endif
-
 // [Debugging]
 //#define IMGUI_IMPL_OPENGL_DEBUG
 #ifdef IMGUI_IMPL_OPENGL_DEBUG
@@ -364,7 +360,7 @@ bool    ImGui_ImplOpenGL3_Init(const char* glsl_version)
 
     // Detect extensions we support
     bd->HasClipOrigin = (bd->GlVersion >= 450);
-#ifdef IMGUI_IMPL_OPENGL_MAY_HAVE_EXTENSIONS
+#ifdef IMGUI_IMPL_OPENGL_HAS_EXTENSIONS
     GLint num_extensions = 0;
     glGetIntegerv(GL_NUM_EXTENSIONS, &num_extensions);
     for (GLint i = 0; i < num_extensions; i++)
@@ -416,7 +412,7 @@ static void ImGui_ImplOpenGL3_SetupRenderState(ImDrawData* draw_data, int fb_wid
     if (bd->GlVersion >= 310)
         glDisable(GL_PRIMITIVE_RESTART);
 #endif
-#ifdef IMGUI_IMPL_HAS_POLYGON_MODE
+#ifdef IMGUI_IMPL_OPENGL_HAS_POLYGON_MODE
     glPolygonMode(GL_FRONT_AND_BACK, GL_FILL);
 #endif
 
@@ -505,7 +501,7 @@ void    ImGui_ImplOpenGL3_RenderDrawData(ImDrawData* draw_data)
 #ifdef IMGUI_IMPL_OPENGL_USE_VERTEX_ARRAY
     GLuint last_vertex_array_object; glGetIntegerv(GL_VERTEX_ARRAY_BINDING, (GLint*)&last_vertex_array_object);
 #endif
-#ifdef IMGUI_IMPL_HAS_POLYGON_MODE
+#ifdef IMGUI_IMPL_OPENGL_HAS_POLYGON_MODE
     GLint last_polygon_mode[2]; glGetIntegerv(GL_POLYGON_MODE, last_polygon_mode);
 #endif
     GLint last_viewport[4]; glGetIntegerv(GL_VIEWPORT, last_viewport);
@@ -644,7 +640,7 @@ void    ImGui_ImplOpenGL3_RenderDrawData(ImDrawData* draw_data)
     if (bd->GlVersion >= 310) { if (last_enable_primitive_restart) glEnable(GL_PRIMITIVE_RESTART); else glDisable(GL_PRIMITIVE_RESTART); }
 #endif
 
-#ifdef IMGUI_IMPL_HAS_POLYGON_MODE
+#ifdef IMGUI_IMPL_OPENGL_HAS_POLYGON_MODE
     // Desktop OpenGL 3.0 and OpenGL 3.1 had separate polygon draw modes for front-facing and back-facing faces of polygons
     if (bd->GlVersion <= 310 || bd->GlProfileIsCompat)
     {
@@ -655,7 +651,7 @@ void    ImGui_ImplOpenGL3_RenderDrawData(ImDrawData* draw_data)
     {
         glPolygonMode(GL_FRONT_AND_BACK, (GLenum)last_polygon_mode[0]);
     }
-#endif // IMGUI_IMPL_HAS_POLYGON_MODE
+#endif // IMGUI_IMPL_OPENGL_HAS_POLYGON_MODE
 
     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]);