glTexCoordPointer -- define an array of texture coordinates.
說明,參數,描述,出錯,
說明
void glTexCoordPointer(GLint size,
GLenum type,
GLsizei stride,
const GLvoid *pointer);
參數
size -- Specifies the number of coordinates per array element. Must be 1,2,3, or 4. The initial value is 4.
type -- Specifies the data type of each texture coordinate. Symbolic constants GL_SHORT, GL_INT, GL_FLOAT, or GL_DOUBLE are accepted. The initial value is GL_FLOAT.
stride -- Specifies the byte offset between consecutive texture coordinate sets. If stride is 0, the array elements are understood to be tightly packed. The initial value is 0.
pointer -- Specifies a pointer to the first coordinate of the first texture coordinate set in the array. The initial value is 0.
描述
glTexCoordPointer specifies the location and data format of an array of texture coordinates to use when rendering. size specifies the number of coordinates per texture coordinate set, and must be 1, 2, 3, or 4. type specifies the data type of each texture coordinate, and stride specifies the byte stride from one texture coordinate set to the next, allowing vertices and attributes to be packed into a single array or stored in separate arrays. (Single-array storage may be more efficient on some implementations.)
If a non-zero named buffer object is bound to the GL_ARRAY_BUFFER target while a texture coordinate array is specified, pointer is treated as a byte offset into the buffer object's data store. Also, the buffer object binding (GL_ARRAY_BUFFER_BINDING) is saved as texture coordinate vertex array client-side state (GL_TEXTURE_COORD_ARRAY_BUFFER_BINDING).
When a texture coordinate array is specified, size, type, stride, and pointer are saved as client-side state, in addition to the current vertex array buffer object binding.
To enable and disable a texture coordinate array, call glEnableClientState and glDisableClientState with the argument GL_TEXTURE_COORD_ARRAY. If enabled, the texture coordinate array is used when glArrayElement, glDrawArrays, glMultiDrawArrays, glDrawElements, glMultiDrawElements, or glDrawRangeElements is called.
出錯
GL_INVALID_VALUE is generated if size is not 1, 2, 3, or 4.
GL_INVALID_ENUM is generated if type is not an accepted value.
GL_INVALID_VALUE is generated if stride is negative.
