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Nintendo® Confidential

## gSPLookAt

Syntax

    #include <ultra64.h> /* gbi.h */
    gSPLookAt(Gfx *gdl, LookAt *l)
    gsSPLookAt(LookAt *l)

Arguments

- gdl is the display list pointer.

- l is the LookAt structure address.

Explanation
gSPLookAt Loads a LookAt structure into the Light buffer in order to perform specular highlighting and reflection mapping. The LookAt structure can be set with the utility commands guLookAtHilite and guLookAtReflect, or it can be set directly with gdSPDefLookAt. The LookAt structure contains colors and the x,y screen coordinates. For details, please see Section 11.7.5.1, Structure Definition" in the N64 Online Programming Manual.

Comment
The LookAt structure is shown below:

    typedef struct {
            unsigned char	col[3];	/* Diffuse light value (RGBA) */
            char		pad1;
            unsigned char	colc[3]; /* Copy of the diffuse light value (RGBA) */
            char		pad2;
            signed char	dir[3];	/* Direction toward the light source (normalized) */
            char		pad3;	/* IMPORTANT: "dir" must be less than 127 */
    } Light_t;
    typedef union {
            Light_t		l;
            long long int	force_structure_alignment[2];
    } Light;
    typedef struct {
            Light		l[2];
    } LookAt;

See Also
gdSPDefLookAt
guLookAtHilite
guLookAtRelect

Revision History
2/1/1999 Completely rewritten.

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Copyright © 1998
Nintendo of America Inc. All rights reserved
Nintendo and N64 are registered trademarks of Nintendo
Last updated March 1999