src/gallium/auxiliary/util/u_viewport.h

   1 /**************************************************************************
   2  *
   3  * Copyright 2016 Ilia Mirkin.
   4  * All Rights Reserved.
   5  *
   6  * Permission is hereby granted, free of charge, to any person obtaining a
   7  * copy of this software and associated documentation files (the
   8  * "Software"), to deal in the Software without restriction, including
   9  * without limitation the rights to use, copy, modify, merge, publish,
  10  * distribute, sub license, and/or sell copies of the Software, and to
  11  * permit persons to whom the Software is furnished to do so, subject to
  12  * the following conditions:
  13  *
  14  * The above copyright notice and this permission notice (including the
  15  * next paragraph) shall be included in all copies or substantial portions
  16  * of the Software.
  17  *
  18  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
  19  * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
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  21  * IN NO EVENT SHALL VMWARE AND/OR ITS SUPPLIERS BE LIABLE FOR
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  25  *
  26  **************************************************************************/
  27
  28 #ifndef U_VIEWPORT_H
  29 #define U_VIEWPORT_H
  30
  31 #include "c99_compat.h"
  32 #include "pipe/p_state.h"
  33
  34 #ifdef __cplusplus
  35 extern "C" {
  36 #endif
  37
  38 static inline void
  39 util_viewport_zmin_zmax(const struct pipe_viewport_state *vp, bool halfz,
  40                         float *zmin, float *zmax)
  41 {
  42    float a, b;
  43    if (halfz) {
  44       a = vp->translate[2];
  45       b = vp->translate[2] + vp->scale[2];
  46    } else {
  47       a = vp->translate[2] - vp->scale[2];
  48       b = vp->translate[2] + vp->scale[2];
  49    }
  50
  51    *zmin = a < b ? a : b;
  52    *zmax = a < b ? b : a;
  53 }
  54
  55 #ifdef __cplusplus
  56 }
  57 #endif
  58
  59 #endif