Graphics.Rendering.OpenGL.GL.PrimitiveMode

This module corresponds to section 10.1 (Primitive Types) of the OpenGL 4.4 specs.

Primitive Modes

data PrimitiveMode

Specification of the way the vertices given during renderPrimitive are interpreted. In the description of the constructors, n is an integer count starting at one, and N is the total number of vertices specified.

Constructors

Points

Treats each vertex as a single point. Vertex n defines point n. N points are drawn.

Lines

Treats each pair of vertices as an independent line segment. Vertices 2n-1 and 2n define line n. N/2 lines are drawn.

LineLoop

Draws a connected group of line segments from the first vertex to the last, then back to the first. Vertices n and n+1 define line n. The last line, however, is defined by vertices N and 1. N lines are drawn.

LineStrip

Draws a connected group of line segments from the first vertex to the last. Vertices n and n+1 define line n. N-1 lines are drawn.

Triangles

Treats each triplet of vertices as an independent triangle. Vertices 3n-2, 3n-1, and 3n define triangle n. N/3 triangles are drawn.

TriangleStrip

Draws a connected group of triangles. One triangle is defined for each vertex presented after the first two vertices. For odd n, vertices n, n+1, and n+2 define triangle n. For even n, vertices n+1, n, and n+2 define triangle n. N-2 triangles are drawn.

TriangleFan

Draws a connected group of triangles. One triangle is defined for each vertex presented after the first two vertices. Vertices 1, n+1, and n+2 define triangle n. N-2 triangles are drawn.

Quads

Treats each group of four vertices as an independent quadrilateral. Vertices 4n-3, 4n-2, 4n-1, and 4n define quadrilateral n. N/4 quadrilaterals are drawn.

QuadStrip

Draws a connected group of quadrilaterals. One quadrilateral is defined for each pair of vertices presented after the first pair. Vertices 2n-1, 2n, 2n+2, and 2n+1 define quadrilateral n. N/2-1 quadrilaterals are drawn. Note that the order in which vertices are used to construct a quadrilateral from strip data is different from that used with independent data.

Polygon

Draws a single, convex polygon. Vertices 1 through N define this polygon.

Patches

Only used in conjunction with tessellation. The number of vertices per patch can be set with patchVertices.

Instances

Eq PrimitiveMode

Ord PrimitiveMode

Show PrimitiveMode

Patches (Tessellation)

patchVertices :: StateVar GLsizei

patchVertices is the number of vertices per patch primitive.

An InvalidValue is generated if patchVertices is set to a value less than or equal to zero or greater than the implementation-dependent maximum value maxPatchVertices.

maxPatchVertices :: GettableStateVar GLsizei

Contains the maximumum number of vertices in a single patch.

patchDefaultOuterLevel :: StateVar (GLfloat, GLfloat, GLfloat, GLfloat)

Contains the four default outer tessellation levels to be used when no tessellation control shader is present.

patchDefaultInnerLevel :: StateVar (GLfloat, GLfloat)

Contains the two default inner tessellation levels to be used when no tessellation control shader is present.

maxTessGenLevel :: GettableStateVar GLsizei

Contains the maximum allowed tessellation level.