From 44bb24bbaf13d1ab236e400a096c12b1859e564b Mon Sep 17 00:00:00 2001
From: Bill Currie <bill@taniwha.org>
Date: Sun, 25 Feb 2024 11:12:10 +0900
Subject: [PATCH] [glsl] Add support for debug callback

It's disabled at compile time for now, but everything needed is there.
---
 include/QF/GLSL/defines.h                  | 13 ++++++++++
 include/QF/GLSL/qf_funcs_list.h            |  2 ++
 include/QF/GLSL/types.h                    |  2 ++
 libs/video/renderer/glsl/vid_common_glsl.c | 30 ++++++++++++++++++++++
 4 files changed, 47 insertions(+)

diff --git a/include/QF/GLSL/defines.h b/include/QF/GLSL/defines.h
index b06041469..c866cea43 100644
--- a/include/QF/GLSL/defines.h
+++ b/include/QF/GLSL/defines.h
@@ -435,4 +435,17 @@
 
 #define GL_INVALID_FRAMEBUFFER_OPERATION  0x0506
 
+#define GL_DEBUG_TYPE_ERROR 0x824C
+#define GL_DEBUG_TYPE_DEPRECATED_BEHAVIOR 0x824D
+#define GL_DEBUG_TYPE_UNDEFINED_BEHAVIOR 0x824E
+#define GL_DEBUG_TYPE_PORTABILITY 0x824F
+#define GL_DEBUG_TYPE_PERFORMANCE 0x8250
+#define GL_DEBUG_TYPE_OTHER 0x8251
+#define GL_DEBUG_SEVERITY_HIGH 0x9146
+#define GL_DEBUG_SEVERITY_MEDIUM 0x9147
+#define GL_DEBUG_SEVERITY_LOW 0x9148
+#define GL_DEBUG_SEVERITY_NOTIFICATION 0x826B
+#define GL_DEBUG_OUTPUT 0x92E0
+
+
 #endif//__glsl_defines_h
diff --git a/include/QF/GLSL/qf_funcs_list.h b/include/QF/GLSL/qf_funcs_list.h
index 26adfea69..dca881ed8 100644
--- a/include/QF/GLSL/qf_funcs_list.h
+++ b/include/QF/GLSL/qf_funcs_list.h
@@ -163,6 +163,8 @@ QFGL_NEED (void, glVertexAttrib4fv, (GLuint indx, const GLfloat* values))
 QFGL_NEED (void, glVertexAttribPointer, (GLuint indx, GLint size, GLenum type, GLboolean normalized, GLsizei stride, const GLvoid* ptr))
 QFGL_NEED (void, glViewport, (GLint x, GLint y, GLsizei width, GLsizei height))
 
+QFGL_NEED (void, glDebugMessageCallback, (GLDEBUGPROC callback, const void *userParam))
+
 #ifdef UNDEF_QFGL_DONT_NEED
 #undef QFGL_DONT_NEED
 #endif
diff --git a/include/QF/GLSL/types.h b/include/QF/GLSL/types.h
index 3e0819fa9..65c15a564 100644
--- a/include/QF/GLSL/types.h
+++ b/include/QF/GLSL/types.h
@@ -44,4 +44,6 @@ typedef ptrdiff_t        GLfixed;
 typedef ptrdiff_t        GLintptr;
 typedef ptrdiff_t        GLsizeiptr;
 
+typedef void (GLAPIENTRY *GLDEBUGPROC) (GLenum source, GLenum type, GLuint id, GLenum severity, GLsizei length, const GLchar *message, const void *userParam);
+
 #endif//__QF_GLSL_types_h
diff --git a/libs/video/renderer/glsl/vid_common_glsl.c b/libs/video/renderer/glsl/vid_common_glsl.c
index e03060f68..c386e21ec 100644
--- a/libs/video/renderer/glsl/vid_common_glsl.c
+++ b/libs/video/renderer/glsl/vid_common_glsl.c
@@ -153,6 +153,31 @@ GLSL_Shutdown_Common (void)
 	GLSL_ShaderShutdown ();
 }
 
+static void
+debug_breakpoint (GLenum type)
+{
+	exit (1);
+}
+
+static void
+MessageCallback (GLenum source, GLenum type, GLuint id, GLenum severity,
+				 GLsizei length, const GLchar *message, const void *uparam)
+{
+	if (type == GL_DEBUG_TYPE_OTHER
+		&& severity == GL_DEBUG_SEVERITY_NOTIFICATION) {
+			return;
+	}
+	if (type != GL_DEBUG_TYPE_PERFORMANCE) {
+		fprintf (stderr,
+				 "GL CALLBACK: %s type = 0x%x, severity = 0x%x, message = %s\n",
+				 ( type == GL_DEBUG_TYPE_ERROR ? "** GL ERROR **" : "" ),
+			     type, severity, message );
+	}
+	if (type == GL_DEBUG_TYPE_ERROR) {
+		debug_breakpoint (type);
+	}
+}
+
 void
 GLSL_Init_Common (void)
 {
@@ -160,6 +185,11 @@ GLSL_Init_Common (void)
 
 	GLSL_Common_Init_Cvars ();
 
+	if (0) {
+		qfeglEnable (GL_DEBUG_OUTPUT);
+		qfeglDebugMessageCallback (MessageCallback, nullptr);
+	}
+
 	GLSL_TextureInit ();
 
 	if (developer & SYS_glsl) {