Applies to: desktop apps only
The glBegin and glend functions delimit the vertices of a primitive or a group of like primitives.
void WINAPI glBegin( GLenum mode );
The primitive or primitives that will be created from vertices presented between glBegin and the subsequent glEnd. The following are accepted symbolic constants and their meanings:
This function does not return a value.
The following error codes can be retrieved by the glGetError function.
mode was set to an unaccepted value.
A function other than glVertex, glColor, glIndex, glNormal, glTexCoord, glEvalCoord, glEvalPoint, glMaterial, glEdgeFlag, glCallList, or glCallLists was called between glBegin and the corresponding glEnd. The function glEnd was called before the corresponding glBegin was called, or glBegin was called within a glBegin/glEnd sequence.
The glBegin and glend functions delimit the vertices that define a primitive or a group of like primitives. The glBegin function accepts a single argument that specifies which of ten primitives the vertices compose. Taking n as an integer count starting at one, and N as the total number of vertices specified, the interpretations are as follows:
- You can use only a subset of OpenGL functions between glBegin and glEnd. The functions you can use are:
You can also use glCallList or glCallLists to execute display lists that include only the preceding functions. If any other OpenGL function is called between glBegin and glEnd, the error flag is set and the function is ignored.
- Regardless of the value chosen for mode in glBegin, there is no limit to the number of vertices you can define between glBegin and glEnd. Lines, triangles, quadrilaterals, and polygons that are incompletely specified are not drawn. Incomplete specification results when either too few vertices are provided to specify even a single primitive or when an incorrect multiple of vertices is specified. The incomplete primitive is ignored; the complete primitives are drawn.
- The minimum specification of vertices for each primitive is:
Minimum number of vertices Type of primitive 1 point 2 line 3 triangle 4 quadrilateral 3 polygon
- Modes that require a certain multiple of vertices are GL_LINES (2), GL_TRIANGLES (3), GL_QUADS (4), and GL_QUAD_STRIP (2).
Minimum supported client
|Windows 2000 Professional|
Minimum supported server
|Windows 2000 Server|
Build date: 3/6/2012