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gdSPDefLookAt

Syntax
#include "gbi.h"
typedef union {
Light    l[2];
} LookAt;
LookAt gdSPDefLookAt(signed char rightx,
     signed char righty,
     signed char rightz,
     signed char upx,
     signed char upy,
     signed char upz)
Arguments
  • rightx, righty, rightz are the x, y, z components in viewing space of x direction in screen space
  • upx, upy, upz are the x, y, z components in viewing space of y direction in screen space
Explanation
It loads the x and y screen space coordinate directions into a LookAt structure. The x and y direction unit vectors, where components are expressed in the viewing space, must be converted to a signed 8-bit fixed-point representation. Each component c must undergo the conversion:

((int) MIN(((c) * (128.0)),127.0) 0xff)

The LookAt structure serves as input for the gSPLookAt macro, used in the set up process for specular highlights or reflection mapping.

See Also
gSPLookAt


Nintendo® Confidential

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