glTexSubImage1DEXT Subroutine

OpenGL 1.1 for AIX: Reference Manual

glTexSubImage1DEXT Subroutine

Purpose

Specifies a one-dimensional texture subimage.

Library

OpenGL C bindings library: libGL.a

C Syntax

void glTexSubImage1DEXT(GLenum target, 
                  GLint level, 
                  GLint xoffset, 
                  GLsizei width, 
                  GLenum format, 
                  GLenum type, 
                  const GLvoid *pixels)

Parameters

target	Specifies the target texture. Must be GL_TEXTURE_1D
level	Specifies the level-of-detail number. Level 0 is the base image level. Level n is the nth mipmap reduction image.
xoffset	Specifies a texel offset in the x direction within the texture array.
width	Specifies the width of the texture subimage.
format	Specifies the format of the pixel data. The following symbolic values are accepted: GL_COLOR_INDEX, GL_RED, GL_GREEN, GL_BLUE, GL_ALPHA, GL_RGB, GL_RGBA, GL_ABGR_EXT, GL_LUMINANCE, and GL_LUMINANCE_ALPHA.
type	Specifies the data type of the pixel data. The following symbolic values are accepted: GL_UNSIGNED_BYTE, GL_BYTE, GL_BITMAP, GL_UNSIGNED_SHORT, GL_SHORT, GL_UNSIGNED_INT, GL_INT, and GL_FLOAT.
pixels	Specifies a pointer to the image data in memory.

Description

Texturing maps a portion of a specified texture image onto each graphical primitive for which texturing is enabled. One-dimensional texturing is enabled and disabled using glEnable and glDisable with argument GL_TEXTURE_1D.

glTexSubImage1DEXT redefines a contiguous subregion of an existing one-dimensional texture image. The texels referenced by pixels replace the portion of the existing texture array with x indices xoffset and xoffset+width-1, inclusive. This region may not include any texels outside the range of the texture array as it was originally specified. It is not an error to specify a subtexture with zero width, but such a specification has no effect.

Notes

Texturing has no effect in color index mode.

glPixelStore and glPixelTransfer modes affect texture images in exactly the way they affect glDrawPixels.

Format of GL_ABGR_EXT is part of the _extname (EXT_abgr) extension, not part of the core GL command set.

Errors

GL_INVALID_ENUM is generated when target is not one of the allowable values.

GL_INVALID_OPERATION is generated when the texture array has not been defined by a previous glTexImage1D operation.

GL_INVALID_VALUE is generated if level is less than zero or greater than log2(max), where max is the returned value of GL_MAX_TEXTURE_SIZE.

GL_INVALID_VALUE is generated if width <-TEXTURE_BORDER, where TEXTURE_BORDER is the border width of the texture array.

GL_INVALID_VALUE is generated if xoffset <-TEXTURE_BORDER, (xoffset+width) > (TEXTURE_WIDTH- TEXTURE_BORDER). Where TEXTURE_WIDTH and TEXTURE_BORDER are the state values of the texture image being modified. Note that TEXTURE_WIDTH includes twice the border width.

GL_INVALID_ENUM is generated when format is not an accepted format constant.

GL_INVALID_ENUM is generated when type is not a type constant.

GL_INVALID_ENUM is generated if type is GL_BITMAP and format is not GL_COLOR_INDEX.

GL_INVALID_OPERATION is generated if glTexSubImage1DEXT is executed between the execution of glBegin and the corresponding execution of glEnd.

Associated Gets

glGetTexImage

glIsEnabled with argument GL_TEXTURE_1D

File

/usr/include/GL/glext.h

Contains extensions to C language constants, variable type definitions, and ANSI function prototypes for OpenGL.

Related Information

The glDrawPixels subroutine, glFog subroutine, glPixelStore subroutine, glPixelTransfer subroutine, glTexEnv subroutine, glTexGen subroutine, glTexImage1D subroutine, glTexParameter subroutine.