//
//------------------------------------------------------------
// Copyright(c) 2009-2010 by Digital Media Professionals Inc.
// All rights reserved.
//------------------------------------------------------------
// This source code is the confidential and proprietary
// of Digital Media Professionals Inc.
//------------------------------------------------------------
//

#include "Commonasm.h"

// Input registers map
#define aPosition       v0
#define aNormal         v1
#define aTexCoord       v2

// Output registers map
#define vPosition       o0
#define vQuaternion     o1
#define vView           o2
#define vTexCoord0      o3

#pragma bind_symbol( aPosition.xyzw,  v0, v0 )
#pragma bind_symbol( aNormal.xyz,     v1, v1 )
#pragma bind_symbol( aTexCoord.xy,    v2, v2 )

#pragma bind_symbol( uProjection, c0, c3 )
#pragma bind_symbol( uModelView, c4, c7 )

#pragma output_map ( position, o0 )
#pragma output_map ( quaternion, o1 )
#pragma output_map ( view, o2 )
#pragma output_map ( texture0, o3.xy )


l_position_view_quaternion:

    m4x4    TEMP_VIEW,          dmp_position,       dmp_local_to_view_matrix    // Generate the model view matrix.
    mov     dmp_lrView,         -TEMP_VIEW                                      // Outputs view vector.

    m3x3    TEMP_NORM.xyz,      dmp_normal,         dmp_local_to_view_matrix    // Inner product of normal and view.
    m4x4    gl_Position,        TEMP_VIEW,          dmp_projection_matrix       // Model view projection.

    // Quaternion.
    add     r4,                 TEMP_NORM.z,        CONST_1
    mul     r4,                 r4,                 CONST_HALF
    mov     dmp_lrQuat.w,       CONST_0
    rsq     r4,                 r4.x
    mul     r5,                 TEMP_NORM,          CONST_HALF
    cmp     EQ, EQ,             TEMP_NORM.z,        -CONST_1
    ifc 0, 1, COND_MODE_STA0
        rcp     dmp_lrQuat.z,   r4.x
        mul     dmp_lrQuat.xy,   r5,                 r4
    else
        mov    dmp_lrQuat.xyz, CONST_1_0
    endif
    nop
    ret
    nop

main:
    call    l_position_view_quaternion
    mov     gl_TexCoord0,       aTexCoord

    end
endmain: