Graphics Reference
In-Depth Information
bvec lessThan(ivec x, ivec y)
bvec lessThan(ivec x, ivec y)
Returns the component-wise compare of
x
<
y
.
bvec lessThanEqual(ivec x, ivec y)
bvec lessThanEqual(ivec x, ivec y)
Returns the component-wise compare of
x
<=
y
.
Returns the component-wise compare of
x
>
y
.
bvec greaterThan(vec x, vec y)
bvec greaterThan(ivec x, ivec y)
Returns the component-wise compare of
x
>=
y
.
bvec greaterThanEqual(ivec x, ivec y)
bvec greaterThanEqual(ivec x, ivec y)
bvec equal(ivec x, ivec y)
bvec equal(ivec x, ivec y)
bvec equal(bvec x, bvec y)
Returns the component-wise compare of
x
==
y
.
Returns the component-wise compare of
x
!=
y
.
bvec notEqual(ivec x, ivec y)
bvec notEqual(ivec x, ivec y)
bvec notEqual(bvec x, bvec y)
The vector equivalent of the logical
or
, |—returns true if
any component of
x
is true.
bool any(bvec x)
The vector equivalent of the logical
and
, &—returns true
only if all components of
x
are true.
bool all(bvec x)
The vector equivalent of the logical
not
, !—returns the
component-wise logical complement of
x
.
bvec not(bvec x)
Texture Lookup Functions
The built-in texture lookup functions give you access to textures through sam-
plers, as set up through the OpenGL API. A texture sampler is a GLSL uniform
variable that has been previously associated with a particular texture unit. The
texture unit acts as a pointer to the texture data itself and its sampling informa-
tion, such as size, pixel format, number of dimensions, filtering methods, and
number of mip-map levels. These texture properties are taken into account as
the texture is accessed.
Texture lookup functions can be used by both vertex and fragment shad-
ers. However, level of detail is not computed by fixed functionality for vertex
shaders, so there are some differences in operation between vertex and frag-
ment texture lookups.
