org.lwjgl.opengl

Class ARBProvokingVertex

java.lang.Object

org.lwjgl.opengl.ARBProvokingVertex

public class ARBProvokingVertex
extends java.lang.Object

Native bindings to the ARB_provoking_vertex extension.

This extension provides an alternative provoking vertex convention for rendering lines, triangles, and (optionally depending on the implementation) quads.

The provoking vertex of a primitive is the vertex that determines the constant primary and secondary colors when flat shading is enabled.

In OpenGL, the provoking vertex for triangle, quad, line, and (trivially) point primitives is the last vertex used to assemble the primitive. The polygon primitive is an exception in OpenGL where the first vertex of a polygon primitive determines the color of the polygon, even if actually broken into triangles and/or quads.

Alternatively the provoking vertex could be the first vertex of the primitive. Other APIs with flat-shading functionality such as Reality Lab and Direct3D have adopted the "first vertex of the primitive" convention to determine the provoking vertex. However, these APIs lack quads so do not have a defined provoking vertex convention for quads.

The motivation for this extension is to allow applications developed for APIs with a "first vertex of the primitive" provoking vertex to be easily converted to OpenGL.

Promoted to core in OpenGL 3.2.

Field Summary

Fields

Modifier and Type	Field and Description
static int	GL_FIRST_VERTEX_CONVENTION Accepted by the mode parameter of ProvokingVertex.
static int	GL_LAST_VERTEX_CONVENTION Accepted by the mode parameter of ProvokingVertex.
static int	GL_PROVOKING_VERTEX Accepted by the pname parameter of GetBooleanv, GetIntegerv, GetFloatv, and GetDoublev.
static int	GL_QUADS_FOLLOW_PROVOKING_VERTEX_CONVENTION Accepted by the pname parameter of GetBooleanv, GetIntegerv, GetFloatv, and GetDoublev.

Method Summary

Modifier and Type	Method and Description
static void	glProvokingVertex(int mode) Specifies the vertex to be used as the source of data for flat shaded varyings.

Methods inherited from class java.lang.Object

equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

GL_FIRST_VERTEX_CONVENTION

public static final int GL_FIRST_VERTEX_CONVENTION

Accepted by the mode parameter of ProvokingVertex.

See Also:

Constant Field Values

GL_LAST_VERTEX_CONVENTION

public static final int GL_LAST_VERTEX_CONVENTION

Accepted by the mode parameter of ProvokingVertex.

See Also:

Constant Field Values

GL_PROVOKING_VERTEX

public static final int GL_PROVOKING_VERTEX

Accepted by the pname parameter of GetBooleanv, GetIntegerv, GetFloatv, and GetDoublev.

See Also:

Constant Field Values

GL_QUADS_FOLLOW_PROVOKING_VERTEX_CONVENTION

public static final int GL_QUADS_FOLLOW_PROVOKING_VERTEX_CONVENTION

Accepted by the pname parameter of GetBooleanv, GetIntegerv, GetFloatv, and GetDoublev.

See Also:

Constant Field Values

Method Detail

glProvokingVertex

public static void glProvokingVertex(int mode)

Specifies the vertex to be used as the source of data for flat shaded varyings.

Parameters:

mode - the provoking vertex mode. One of:

FIRST_VERTEX_CONVENTION

LAST_VERTEX_CONVENTION