GLAPI/glGetDebugMessageLog

From OpenGL.org
Jump to: navigation, search
glGetDebugMessageLog
Core in version 4.5
Core since version 4.3
Core ARB extension KHR_debug

glGetDebugMessageLog: retrieve messages from the debug message log

Function Definition

 GLuint glGetDebugMessageLog(GLuint count​, GLsizei bufSize​, GLenum *sources​, Glenum *types​, GLuint *ids​, GLenum *severities​, GLsizei *lengths​, GLchar *messageLog​);
count
The number of debug messages to retrieve from the log.
bufSize
The size of the buffer whose address is given by messageLog​.
sources
The address of an array of variables to receive the sources of the retrieved messages. Each value may be GL_DEBUG_SOURCE_API (for messages generated by the GL), GL_DEBUG_SOURCE_SHADER_COMPILER (for messages generated by the GLSL shader compiler of compilers for other extension-provided languages), GL_DEBUG_SOURCE_WINDOW_SYSTEM (for messages generated by the window system, such as WGL or GLX), GL_DEBUG_SOURCE_THIRD_PARTY (for messages generated by external debuggers or third-party middle-ware libraries), GL_DEBUG_SOURCE_APPLICATION (for messages generated by the application, such as through glDebugMessageInsert), or GL_DEBUG_SOURCE_OTHER (for messages that do not fit to any of the other sources).
types
The address of an array of variables to receive the types of the retrieved messages. Each value may be GL_DEBUG_TYPE_ERROR (for events that generated an error), GL_DEBUG_TYPE_DEPRECATED_BEHAVIOR (for behaviour that has been marked for deprecation), GL_DEBUG_TYPE_UNDEFINED_BEHAVIOR (for behaviour that is undefined according to the specification), GL_DEBUG_TYPE_PERFORMANCE (for implementation-dependent performance warnings), GL_DEBUG_TYPE_PORTABILITY (for the use of extensions or shaders in a way that is highly vendor-specific), GL_DEBUG_TYPE_MARKER (for annotation of the command stream), GL_DEBUG_TYPE_PUSH_GROUP (for entering a debug group with glPushDebugGroup), GL_DEBUG_TYPE_POP_GROUP (for leaving a debug group with glPopDebugGroup), or GL_DEBUG_TYPE_OTHER (for events that don't fit any of the ones listed above).
ids
The address of an array of unsigned integers to receive the IDs of the retrieved messages. The assignment of IDs to messages within a namespace is implementation-dependent. Messages can only be uniquely distinguished from each other by the full combination of source, type, and ID.
severities
The address of an array of variables to receive the severities of the retrieved messages. Each value may be GL_DEBUG_SEVERITY_HIGH (for any GL error, dangerous undefined behaviour, or any shader compiler and linker errors), GL_DEBUG_SEVERITY_MEDIUM (for severe performance warnings, GLSL or other shader compiler and linker warnings, and use of currently deprecated behaviour), GL_DEBUG_SEVERITY_LOW (for performance warnings from redundant state changes and trivial undefined behaviour), GL_DEBUG_SEVERITY_NOTIFICATION (for any message which is not an error or performance concern).
lengths
The address of an array of variables to receive the lengths of the received messages.
messageLog
The address of an array of characters that will receive the messages.

Description

glGetDebugMessageLog retrieves messages from the debug message log. A maximum of count​ messages are retrieved from the log. If sources​ is not NULL then the source of each message is written into up to count​ elements of the array. If types​ is not NULL then the type of each message is written into up to count​ elements of the array. If id​ is not NULL then the identifier of each message is written into up to count​ elements of the array. If severities​ is not NULL then the severity of each message is written into up to count​ elements of the array. If lengths​ is not NULL then the length of each message is written into up to count​ elements of the array.

messageLog​ specifies the address of a character array into which the debug messages will be written. Each message will be concatenated onto the array starting at the first element of messageLog​. bufSize​ specifies the size of the array messageLog​. If a message will not fit into the remaining space in messageLog​ then the function terminates and returns the number of messages written so far, which may be zero.

If glGetDebugMessageLog returns zero then no messages are present in the debug log, or there was not enough space in messageLog​ to retrieve the first message in the queue. If messageLog​ is NULL then no messages are written and the value of bufSize​ is ignored.

Notes

Although debug messages may be enabled in a non-debug context, the quantity and detail of such messages may be substantially inferior to those in a debug context. In particular, a valid implementation of the debug message queue in a non-debug context may produce no messages at all.

Errors

GL_INVALID_VALUE is generated if count​ or bufSize​ is negative.

Associated Gets

glGet with argument GL_DEBUG_LOGGED_MESSAGES

glGet with argument GL_DEBUG_NEXT_LOGGED_MESSAGE_LENGTH

glGet with argument GL_MAX_DEBUG_MESSAGE_LENGTH

glGet with argument GL_MAX_DEBUG_LOGGED_MESSAGES

See Also

glDebugMessageInsert, glDebugMessageCallback, glDebugMessageControl, glPushDebugGroup, glPopDebugGroup

Copyright

Copyright © 2012 Khronos Group. This material may be distributed subject to the terms and conditions set forth in the Open Publication License, v 1.0, 8 June 1999. http://opencontent.org/openpub/.