Practical Algorithms for 3D Computer Graphics, 2nd Edition

11.3. GPU textures 493

void main ( void ){

Compute the tran s fo r med normal

tnorm = NormalMatrix∗VertexNormal ;

Set the built in variable with the vertex po s itio n

g l P o s i t i o n = Mode lV ie wP ro ject ionMatrix ∗Ve r te x Pos i ti o n ;

Copy the vertex position

PP= ModelViewMatrix ∗ V ert e xP o sit i on ;

Pass the vertex position in the texture cell and

the texture cell edge vectors to fragment program

te xp os = Sha der Pos it i on ;

vvec = n or mal iz e ( NormalMatrix ∗ Vvector ) ;

wvec = n or mal iz e ( NormalMatrix ∗ Wvector ) ;

uvec = n orm al iz e ( NormalMatrix ∗ Uvector ) ;

Set color oup tu t variable

Color = Ve rte xCo lor ;

}

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