Backends: OpenGL3: Handle GL_CLIP_ORIGIN on <4.5 contexts if "GL_ARB_clip_control" extension is detected. (#4170, #3998)
Expecting this to somehow cause another issue but we will fix it when it comes.
diff --git a/backends/imgui_impl_opengl3.cpp b/backends/imgui_impl_opengl3.cpp
index 643affe..6017704 100644
--- a/backends/imgui_impl_opengl3.cpp
+++ b/backends/imgui_impl_opengl3.cpp
@@ -13,6 +13,7 @@
// CHANGELOG
// (minor and older changes stripped away, please see git history for details)
+// 2021-05-24: OpenGL: Access GL_CLIP_ORIGIN when "GL_ARB_clip_control" extension is detected, inside of just OpenGL 4.5 version.
// 2021-05-19: OpenGL: Replaced direct access to ImDrawCmd::TextureId with a call to ImDrawCmd::GetTexID(). (will become a requirement)
// 2021-04-06: OpenGL: Don't try to read GL_CLIP_ORIGIN unless we're OpenGL 4.5 or greater.
// 2021-02-18: OpenGL: Change blending equation to preserve alpha in output buffer.
@@ -144,6 +145,11 @@
#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
+
// OpenGL Data
static GLuint g_GlVersion = 0; // Extracted at runtime using GL_MAJOR_VERSION, GL_MINOR_VERSION queries (e.g. 320 for GL 3.2)
static char g_GlslVersionString[32] = ""; // Specified by user or detected based on compile time GL settings.
@@ -152,6 +158,7 @@
static GLint g_AttribLocationTex = 0, g_AttribLocationProjMtx = 0; // Uniforms location
static GLuint g_AttribLocationVtxPos = 0, g_AttribLocationVtxUV = 0, g_AttribLocationVtxColor = 0; // Vertex attributes location
static unsigned int g_VboHandle = 0, g_ElementsHandle = 0;
+static bool g_HasClipOrigin = false;
// Functions
bool ImGui_ImplOpenGL3_Init(const char* glsl_version)
@@ -231,6 +238,19 @@
GLint current_texture;
glGetIntegerv(GL_TEXTURE_BINDING_2D, ¤t_texture);
+ // Detect extensions we support
+ g_HasClipOrigin = (g_GlVersion >= 450);
+#ifdef IMGUI_IMPL_OPENGL_MAY_HAVE_EXTENSIONS
+ GLint num_extensions = 0;
+ glGetIntegerv(GL_NUM_EXTENSIONS, &num_extensions);
+ for (GLint i = 0; i < num_extensions; i++)
+ {
+ const char* extension = (const char*)glGetStringi(GL_EXTENSIONS, i);
+ if (strcmp(extension, "GL_ARB_clip_control") == 0)
+ g_HasClipOrigin = true;
+ }
+#endif
+
return true;
}
@@ -266,7 +286,7 @@
// Support for GL 4.5 rarely used glClipControl(GL_UPPER_LEFT)
#if defined(GL_CLIP_ORIGIN)
bool clip_origin_lower_left = true;
- if (g_GlVersion >= 450)
+ if (g_HasClipOrigin)
{
GLenum current_clip_origin = 0; glGetIntegerv(GL_CLIP_ORIGIN, (GLint*)¤t_clip_origin);
if (current_clip_origin == GL_UPPER_LEFT)
diff --git a/docs/CHANGELOG.txt b/docs/CHANGELOG.txt
index 7cb7ac4..b51f1fc 100644
--- a/docs/CHANGELOG.txt
+++ b/docs/CHANGELOG.txt
@@ -32,6 +32,14 @@
-----------------------------------------------------------------------
+ VERSION 1.84 WIP (In Progress)
+-----------------------------------------------------------------------
+
+Other Changes:
+- Backends: OpenGL3: Handle GL_CLIP_ORIGIN on <4.5 contexts if "GL_ARB_clip_control" extension is detected. (#4170, #3998)
+
+
+-----------------------------------------------------------------------
VERSION 1.83 (Released 2011-05-24)
-----------------------------------------------------------------------
diff --git a/imgui.h b/imgui.h
index 06a610d..388ef5e 100644
--- a/imgui.h
+++ b/imgui.h
@@ -61,7 +61,7 @@
// Version
// (Integer encoded as XYYZZ for use in #if preprocessor conditionals. Work in progress versions typically starts at XYY99 then bounce up to XYY00, XYY01 etc. when release tagging happens)
#define IMGUI_VERSION "1.83"
-#define IMGUI_VERSION_NUM 18300
+#define IMGUI_VERSION_NUM 18301
#define IMGUI_CHECKVERSION() ImGui::DebugCheckVersionAndDataLayout(IMGUI_VERSION, sizeof(ImGuiIO), sizeof(ImGuiStyle), sizeof(ImVec2), sizeof(ImVec4), sizeof(ImDrawVert), sizeof(ImDrawIdx))
#define IMGUI_HAS_TABLE
