Method GL.glTexSubImage1D()

Method glTexSubImage1D

void glTexSubImage1D(int target, int level, int xoffset, object|mapping(string:object) width, object|mapping(string:object) format, object|mapping(string:object) type, array(object|mapping(string:object)) pixels)

Description

Texturing maps a portion of a specified texture image onto each graphical primitive for which texturing is enabled. To enable or disable one-dimensional texturing, call glEnable and glDisable with argument GL_TEXTURE_1D.

glTexSubImage1D 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 width of 0, but such a specification has no effect.

Parameter target

Specifies the target texture. Must be GL_TEXTURE_1D.

Parameter level

Specifies the level-of-detail number. Level 0 is the base image level. Level n is the nth mipmap reduction image.

Parameter xoffset

Specifies a texel offset in the x direction within the texture array.

Parameter width

Specifies the width of the texture subimage.

Parameter 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_LUMINANCE, and GL_LUMINANCE_ALPHA.

Parameter 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.

Parameter pixels

Specifies a pointer to the image data in memory.

Throws

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

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

GL_INVALID_VALUE is generated if level is less than 0. .P GL_INVALID_VALUE may be generated if level is greater than log sub 2max, where max is the returned value of GL_MAX_TEXTURE_SIZE.

GL_INVALID_VALUE is generated if "xoffset" ~<~ ~-b, or if ("xoffset"~+~"width") ~>~ (w ~-~ b). Where w is the GL_TEXTURE_WIDTH, and b is the width of the GL_TEXTURE_BORDER of the texture image being modified. Note that w includes twice the border width.

GL_INVALID_VALUE is generated if width is less than 0.

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

GL_INVALID_ENUM is generated if 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 glTexSubImage1D is executed between the execution of glBegin and the corresponding execution of glEnd.