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/* $Id: s_histogram.c,v 1.1 2003-02-28 11:49:42 pj Exp $ */
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/*
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 * Mesa 3-D graphics library
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 * Version:  3.5
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 *
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 * Copyright (C) 1999-2001  Brian Paul   All Rights Reserved.
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 *
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 * Permission is hereby granted, free of charge, to any person obtaining a
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 * copy of this software and associated documentation files (the "Software"),
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 * to deal in the Software without restriction, including without limitation
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 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
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 * and/or sell copies of the Software, and to permit persons to whom the
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 * Software is furnished to do so, subject to the following conditions:
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 *
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 * The above copyright notice and this permission notice shall be included
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 * in all copies or substantial portions of the Software.
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 *
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 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
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 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
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 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
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 * BRIAN PAUL BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
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 * AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
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 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
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 */
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#include "glheader.h"
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#include "colormac.h"
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#include "image.h"
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#include "mmath.h"
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#include "s_context.h"
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#include "s_histogram.h"
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#include "s_span.h"
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/*
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 * Update the min/max values from an array of fragment colors.
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 */
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void
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_mesa_update_minmax(GLcontext *ctx, GLuint n, const GLfloat rgba[][4])
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{
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   GLuint i;
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   for (i = 0; i < n; i++) {
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      /* update mins */
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      if (rgba[i][RCOMP] < ctx->MinMax.Min[RCOMP])
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         ctx->MinMax.Min[RCOMP] = rgba[i][RCOMP];
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      if (rgba[i][GCOMP] < ctx->MinMax.Min[GCOMP])
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         ctx->MinMax.Min[GCOMP] = rgba[i][GCOMP];
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      if (rgba[i][BCOMP] < ctx->MinMax.Min[BCOMP])
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         ctx->MinMax.Min[BCOMP] = rgba[i][BCOMP];
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      if (rgba[i][ACOMP] < ctx->MinMax.Min[ACOMP])
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         ctx->MinMax.Min[ACOMP] = rgba[i][ACOMP];
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      /* update maxs */
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      if (rgba[i][RCOMP] > ctx->MinMax.Max[RCOMP])
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         ctx->MinMax.Max[RCOMP] = rgba[i][RCOMP];
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      if (rgba[i][GCOMP] > ctx->MinMax.Max[GCOMP])
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         ctx->MinMax.Max[GCOMP] = rgba[i][GCOMP];
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      if (rgba[i][BCOMP] > ctx->MinMax.Max[BCOMP])
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         ctx->MinMax.Max[BCOMP] = rgba[i][BCOMP];
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      if (rgba[i][ACOMP] > ctx->MinMax.Max[ACOMP])
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         ctx->MinMax.Max[ACOMP] = rgba[i][ACOMP];
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   }
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}
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/*
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 * Update the histogram values from an array of fragment colors.
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 */
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void
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_mesa_update_histogram(GLcontext *ctx, GLuint n, const GLfloat rgba[][4])
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{
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   const GLint max = ctx->Histogram.Width - 1;
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   GLfloat w = (GLfloat) max;
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   GLuint i;
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   if (ctx->Histogram.Width == 0)
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      return;
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   for (i = 0; i < n; i++) {
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      GLint ri = IROUND(rgba[i][RCOMP] * w);
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      GLint gi = IROUND(rgba[i][GCOMP] * w);
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      GLint bi = IROUND(rgba[i][BCOMP] * w);
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      GLint ai = IROUND(rgba[i][ACOMP] * w);
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      ri = CLAMP(ri, 0, max);
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      gi = CLAMP(gi, 0, max);
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      bi = CLAMP(bi, 0, max);
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      ai = CLAMP(ai, 0, max);
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      ctx->Histogram.Count[ri][RCOMP]++;
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      ctx->Histogram.Count[gi][GCOMP]++;
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      ctx->Histogram.Count[bi][BCOMP]++;
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      ctx->Histogram.Count[ai][ACOMP]++;
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   }
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}