glRasterPos, glRasterPos2d, glRasterPos2f, glRasterPos2i,
glRasterPos2s, glRasterPos3d, glRasterPos3f, glRasterPos3i,
glRasterPos3s, glRasterPos4d, glRasterPos4f,
glRasterPos4i, glRasterPos4s, glRasterPos2dv, glRasterPos2fv,
glRasterPos2iv, glRasterPos2sv, glRasterPos3dv,
glRasterPos3fv, glRasterPos3iv, glRasterPos3sv, glRasterPos4dv,
glRasterPos4fv, glRasterPos4iv, glRasterPos4sv -
specify the raster position for pixel operations
void glRasterPos2d(
GLdouble x,
GLdouble y ); void glRasterPos2f(
GLfloat x,
GLfloat y ); void glRasterPos2i(
GLint x,
GLint y ); void glRasterPos2s(
GLshort x,
GLshort y ); void glRasterPos3d(
GLdouble x,
GLdouble y,
GLdouble z ); void glRasterPos3f(
GLfloat x,
GLfloat y,
GLfloat z ); void glRasterPos3i(
GLint x,
GLint y,
GLint z ); void glRasterPos3s(
GLshort x,
GLshort y,
GLshort z ); void glRasterPos4d(
GLdouble x,
GLdouble y,
GLdouble z,
GLdouble w ); void glRasterPos4f(
GLfloat x,
GLfloat y,
GLfloat z,
GLfloat w ); void glRasterPos4i(
GLint x,
GLint y,
GLint z,
GLint w ); void glRasterPos4s(
GLshort x,
GLshort y,
GLshort z,
GLshort w );
Specify the x, y, z, and w object coordinates (if present)
for the raster position.
void glRasterPos2dv(
const GLdouble *v ); void glRasterPos2fv(
const GLfloat *v ); void glRasterPos2iv(
const GLint *v ); void glRasterPos2sv(
const GLshort *v ); void glRasterPos3dv(
const GLdouble *v ); void glRasterPos3fv(
const GLfloat *v ); void glRasterPos3iv(
const GLint *v ); void glRasterPos3sv(
const GLshort *v ); void glRasterPos4dv(
const GLdouble *v ); void glRasterPos4fv(
const GLfloat *v ); void glRasterPos4iv(
const GLint *v ); void glRasterPos4sv(
const GLshort *v );
Specifies a pointer to an array of two, three, or four
elements, specifying x, y, z, and w coordinates, respectively.
The GL maintains a 3D position in window coordinates. This
position, called the raster position, is used to position
pixel and bitmap write operations. It is maintained with
subpixel accuracy. See glBitmap(), glDrawPixels(), and
glCopyPixels().
The current raster position consists of three window coordinates
(x, y, z), a clip coordinate value (w), an eye
coordinate distance, a valid bit, and associated color
data and texture coordinates. The w coordinate is a clip
coordinate, because w is not projected to window coordinates.
glRasterPos4() specifies object coordinates x, y,
z, and w explicitly. glRasterPos3() specifies object
coordinate x, y, and z explicitly, while w is implicitly
set to 1. glRasterPos2() uses the argument values for x
and y while implicitly setting z and w to 0 and 1.
The object coordinates presented by glRasterPos() are
treated just like those of a glVertex() command: They are
transformed by the current modelview and projection matrices
and passed to the clipping stage. If the vertex is not
culled, then it is projected and scaled to window coordinates,
which become the new current raster position, and
the GL_CURRENT_RASTER_POSITION_VALID option is set. If
the vertex is culled, then the valid bit is cleared and
the current raster position and associated color and texture
coordinates are undefined.
The current raster position also includes some associated
color data and texture coordinates. If lighting is
enabled, then GL_CURRENT_RASTER_COLOR (in RGBA mode) or
GL_CURRENT_RASTER_INDEX (in color index mode) is set to
the color produced by the lighting calculation (see
glLight(), glLightModel(), and glShadeModel()). If lighting
is disabled, current color (in RGBA mode, state variable
GL_CURRENT_COLOR) or color index (in color index
mode, state variable GL_CURRENT_INDEX) is used to update
the current raster color.
Likewise, GL_CURRENT_RASTER_TEXTURE_COORDS is updated as a
function of GL_CURRENT_TEXTURE_COORDS, based on the texture
matrix and the texture generation functions (see
glTexGen()). Finally, the distance from the origin of the
eye coordinate system to the vertex as transformed by only
the modelview matrix replaces GL_CURRENT_RASTER_DISTANCE.
Initially, the current raster position is (0, 0, 0, 1),
the current raster distance is 0, the valid bit is set,
the associated RGBA color is (1, 1, 1, 1), the associated
color index is 1, and the associated texture coordinates
are (0, 0, 0, 1). In RGBA mode, GL_CURRENT_RASTER_INDEX is
always 1; in color index mode, the current raster RGBA
color always maintains its initial value.
The raster position is modified both by glRasterPos() and
by glBitmap().
When the raster position coordinates are invalid, drawing
commands that are based on the raster position are ignored
(that is, they do not result in changes to GL state).
Calling glDrawElements(), or glDrawRangeElements() may
leave the current color or index indeterminate. If
glRasterPos() is executed while the current color or index
is indeterminate, the current raster color or current
raster index remains indeterminate.
To set a valid raster position outside the viewport, first
set a valid raster position, then call glBitmap() with
NULL as the bitmap parameter.
When the GL_ARB_imaging extension is supported, there are
distinct raster texture coordinates for each texture unit.
Each texture unit's current ratster texture coordinates
are updated by glRasterPos().
GL_INVALID_OPERATION is generated if glRasterPos() is executed
between the execution of glBegin() and the corresponding
execution of glEnd().
glGet() with argument GL_CURRENT_RASTER_POSITION
glGet() with argument GL_CURRENT_RASTER_POSITION_VALID
glGet() with argument GL_CURRENT_RASTER_DISTANCE
glGet() with argument GL_CURRENT_RASTER_COLOR
glGet() with argument GL_CURRENT_RASTER_INDEX
glGet() with argument GL_CURRENT_RASTER_TEXTURE_COORDS
glBitmap(3), glCopyPixels(3), glDrawArrays(3), glDrawElements(3), glDrawRangeElements(3), glDrawPixels(3), glTexCoord(3), glTexGen(3), glVertex(3)
glRasterPos(3G)
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