OpenGL: don't poll for errors, rely on KHR_debug

Errors are caught & reported by our GL debug callback. This gives us way more useful information than sporadic calls to glGetError.

I removed almost all use of glGetError, including our own GPU_ASSERT_NO_GL_ERRORS and GPU_CHECK_ERRORS_AROUND macros.

Still used in rna_Image_gl_load because it passes unvalidated input to OpenGL functions.

Still used in gpu_state_print_fl_ex as an exception handling hack -- will rewrite this soon.

The optimism embodied by this commit will not prevent OpenGL errors. We need to analyze what would cause GL to fail at certain points and proactively intercept these failures. Or guarantee they can't happen.

1 files changed, 2 insertions, 120 deletions

diff --git a/source/blender/gpu/intern/gpu_debug.c b/source/blender/gpu/intern/gpu_debug.c
index 614fdeb6e85..c25103dd300 100644
--- a/source/blender/gpu/intern/gpu_debug.c
+++ b/source/blender/gpu/intern/gpu_debug.c
@@ -43,113 +43,6 @@
 #include <stdlib.h>
 #include <string.h>
 
-#define CASE_CODE_RETURN_STR(code) case code: return #code;
-
-static const char *gpu_gl_error_symbol(GLenum err)
-{
-	switch (err) {
-		CASE_CODE_RETURN_STR(GL_NO_ERROR)
-		CASE_CODE_RETURN_STR(GL_INVALID_ENUM)
-		CASE_CODE_RETURN_STR(GL_INVALID_VALUE)
-		CASE_CODE_RETURN_STR(GL_INVALID_OPERATION)
-		CASE_CODE_RETURN_STR(GL_STACK_OVERFLOW)
-		CASE_CODE_RETURN_STR(GL_STACK_UNDERFLOW)
-		CASE_CODE_RETURN_STR(GL_OUT_OF_MEMORY)
-
-#if GL_ARB_imaging
-		CASE_CODE_RETURN_STR(GL_TABLE_TOO_LARGE)
-#endif
-
-#if defined(WITH_GLU)
-		CASE_CODE_RETURN_STR(GLU_INVALID_ENUM)
-		CASE_CODE_RETURN_STR(GLU_INVALID_VALUE)
-		CASE_CODE_RETURN_STR(GLU_OUT_OF_MEMORY)
-#endif
-
-		default:
-			return "<unknown error>";
-	}
-}
-
-#undef CASE_CODE_RETURN_STR
-
-
-static bool gpu_report_gl_errors(const char *file, int line, const char *str)
-{
-	GLenum gl_error = glGetError();
-
-	if (gl_error == GL_NO_ERROR) {
-		return true;
-	}
-	else {
-		/* glGetError should have cleared the error flag, so if we get the
-		 * same flag twice that means glGetError itself probably triggered
-		 * the error. This happens on Windows if the GL context is invalid.
-		 */
-		{
-			GLenum new_error = glGetError();
-			if (gl_error == new_error) {
-				fprintf(stderr, "GL: Possible context invalidation issue\n");
-				return false;
-			}
-		}
-
-		fprintf(stderr,
-		        "%s:%d: ``%s'' -> GL Error (0x%04X - %s): %s\n",
-		        file, line, str, gl_error,
-		        gpu_gl_error_symbol(gl_error),
-		        gpuErrorString(gl_error));
-
-		return false;
-	}
-}
-
-
-const char *gpuErrorString(GLenum err)
-{
-	switch (err) {
-		case GL_NO_ERROR:
-			return "No Error";
-
-		case GL_INVALID_ENUM:
-			return "Invalid Enumeration";
-
-		case GL_INVALID_VALUE:
-			return "Invalid Value";
-
-		case GL_INVALID_OPERATION:
-			return "Invalid Operation";
-
-		case GL_STACK_OVERFLOW:
-			return "Stack Overflow";
-
-		case GL_STACK_UNDERFLOW:
-			return "Stack Underflow";
-
-		case GL_OUT_OF_MEMORY:
-			return "Out of Memory";
-
-#if GL_ARB_imaging
-		case GL_TABLE_TOO_LARGE:
-			return "Table Too Large";
-#endif
-
-#if defined(WITH_GLU)
-		case GLU_INVALID_ENUM:
-			return "Invalid Enum (GLU)";
-
-		case GLU_INVALID_VALUE:
-			return "Invalid Value (GLU)";
-
-		case GLU_OUT_OF_MEMORY:
-			return "Out of Memory (GLU)";
-#endif
-
-		default:
-			return "<unknown error>";
-	}
-}
-
 
 /* Debug callbacks need the same calling convention as OpenGL functions.
  */
@@ -400,18 +293,6 @@ void GPU_print_error_debug(const char *str)
 		fprintf(stderr, "GPU: %s\n", str);
 }
 
-
-void GPU_assert_no_gl_errors(const char *file, int line, const char *str)
-{
-	if (G.debug) {
-		GLboolean gl_ok = gpu_report_gl_errors(file, line, str);
-
-		BLI_assert(gl_ok);
-		(void) gl_ok;
-	}
-}
-
-
 static void gpu_state_print_fl_ex(const char *name, GLenum type)
 {
 	const unsigned char err_mark[4] = {0xff, 0xff, 0xff, 0xff};
@@ -438,7 +319,8 @@ static void gpu_state_print_fl_ex(const char *name, GLenum type)
 
 void GPU_state_print(void)
 {
-	GPU_ASSERT_NO_GL_ERRORS("GPU_state_print"); /* clear any errors */
+	/* clear any errors */ 
+	while (glGetError() != GL_NO_ERROR) {} 
 
 	gpu_state_print_fl(GL_ACCUM_ALPHA_BITS);
 	gpu_state_print_fl(GL_ACCUM_BLUE_BITS);