/* GStreamer

 * Copyright (C) <1999> Erik Walthinsen <omega@cse.ogi.edu>

 *

 * This library is free software; you can redistribute it and/or

 * modify it under the terms of the GNU Library General Public

 * License as published by the Free Software Foundation; either

 * version 2 of the License, or (at your option) any later version.

 *

 * This library is distributed in the hope that it will be useful,

 * but WITHOUT ANY WARRANTY; without even the implied warranty of

 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU

 * Library General Public License for more details.

 *

 * You should have received a copy of the GNU Library General Public

 * License along with this library; if not, write to the

 * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,

 * Boston, MA 02110-1301, USA.

 */

#ifdef HAVE_CONFIG_H

#include "config.h"

#endif

#include <math.h>

#include <stdlib.h>

#include "paint.h"

#ifndef M_PI

#define M_PI  3.14159265358979323846

#endif

void

gst_smpte_paint_vbox (guint32 * dest, gint stride,

    gint x0, gint y0, gint c0, gint x1, gint y1, gint c1)

{

  gint i, j;

  gint width, height;

  width = x1 - x0;

  height = y1 - y0;

  g_assert (width > 0);

  g_assert (height > 0);

  dest = dest + y0 * stride + x0;

  for (i = 0; i < height; i++) {

    for (j = 0; j < width; j++) {

      dest[j] = (c1 * j + c0 * (width - j)) / width;

    }

    dest += stride;

  }

}

void

gst_smpte_paint_hbox (guint32 * dest, gint stride,

    gint x0, gint y0, gint c0, gint x1, gint y1, gint c1)

{

  gint i, j;

  gint width, height;

  width = x1 - x0;

  height = y1 - y0;

  g_assert (width > 0);

  g_assert (height > 0);

  dest = dest + y0 * stride + x0;

  for (i = 0; i < height; i++) {

    guint32 value = (c1 * i + c0 * (height - i)) / height;

    for (j = 0; j < width; j++) {

      dest[j] = value;

    }

    dest += stride;

  }

}

#define STEP_3D_LINE(dxabs,dyabs,dzabs,sdx,sdy,sdz,xr,yr,zr,px,py,pz)           \

G_STMT_START {                                          \

  if (dxabs >= dyabs && dxabs >= dzabs) {               \

    yr += dyabs;                                        \

    zr += dzabs;                                        \

    if (yr >= dxabs) {                                  \

      py += sdy;                                        \

      yr -= dxabs;                                      \

    }                                                   \

    if (zr >= dzabs) {                                  \

      pz += sdz;                                        \

      zr -= dxabs;                                      \

    }                                                   \

    px += sdx;                                          \

  } else if (dyabs >= dxabs && dyabs >= dzabs) {        \

    xr += dxabs;                                        \

    zr += dzabs;                                        \

    if (xr >= dyabs) {                                  \

      px += sdx;                                        \

      xr -= dyabs;                                      \

    }                                                   \

    if (zr >= dzabs) {                                  \

      pz += sdz;                                        \

      zr -= dyabs;                                      \

    }                                                   \

    py += sdy;                                          \

  } else {                                              \

    yr += dyabs;                                        \

    xr += dxabs;                                        \

    if (yr >= dyabs) {                                  \

      py += sdy;                                        \

      yr -= dzabs;                                      \

    }                                                   \

    if (xr >= dyabs) {                                  \

      px += sdx;                                        \

      xr -= dzabs;                                      \

    }                                                   \

    pz += sdz;                                          \

  }                                                     \

} G_STMT_END

#define SWAP_INT(a,b)           \

G_STMT_START {                  \

  gint tmp;                     \

  tmp = (a);                    \

  (a) = (b);                    \

  (b) = (tmp);                  \

} G_STMT_END

#define SIGN(a) ((a) < 0 ? -1 : 1)

#define PREPARE_3D_LINE(x0,y0,z0,x1,y1,z1,dxabs,dyabs,dzabs,sdx,sdy,sdz,xr,yr,zr,px,py,pz)\

G_STMT_START {                  \

  gint dx, dy, dz;              \

  dx = x1 - x0;                 \

  dy = y1 - y0;                 \

  dz = z1 - z0;                 \

  dxabs = abs (dx);             \

  dyabs = abs (dy);             \

  dzabs = abs (dz);             \

  sdx = SIGN (dx);              \

  sdy = SIGN (dy);              \

  sdz = SIGN (dz);              \

  xr = dxabs >> 1;              \

  yr = dyabs >> 1;              \

  zr = dzabs >> 1;              \

  px = x0;                      \

  py = y0;                      \

  pz = z0;                      \

} G_STMT_END

void

gst_smpte_paint_triangle_linear (guint32 * dest, gint stride,

    gint x0, gint y0, gint c0,

    gint x1, gint y1, gint c1, gint x2, gint y2, gint c2)

{

  gint sdxl, sdyl, sdcl, dxlabs, dylabs, dclabs, xrl, yrl, crl, pxl, pyl, pcl;

  gint sdxr, sdyr, sdcr, dxrabs, dyrabs, dcrabs, xrr, yrr, crr, pxr, pyr, pcr;

  gint i, j, k, seg_start, seg_end;

  if (y0 > y1) {

    SWAP_INT (x0, x1);

    SWAP_INT (y0, y1);

    SWAP_INT (c0, c1);

  }

  if (y0 > y2) {

    SWAP_INT (x0, x2);

    SWAP_INT (y0, y2);

    SWAP_INT (c0, c2);

  }

  if (y1 > y2) {

    SWAP_INT (x1, x2);

    SWAP_INT (y1, y2);

    SWAP_INT (c1, c2);

  }

  PREPARE_3D_LINE (x0, y0, c0, x2, y2, c2,

      dxlabs, dylabs, dclabs, sdxl, sdyl, sdcl, xrl, yrl, crl, pxl, pyl, pcl);

  PREPARE_3D_LINE (x0, y0, c0, x1, y1, c1,

      dxrabs, dyrabs, dcrabs, sdxr, sdyr, sdcr, xrr, yrr, crr, pxr, pyr, pcr);

  dest = dest + stride * y0;

  seg_start = y0;

  seg_end = y1;

  /* do two passes */

  for (k = 0; k < 2; k++) {

    for (i = seg_start; i < seg_end; i++) {

      gint s = pxl, e = pxr, sc = pcl, ec = pcr;

      gint sign = SIGN (e - s);

      e += sign;

      for (j = s; j != e; j += sign) {

        dest[j] = (ec * (j - s) + sc * (e - j)) / (e - s);

      }

      while (pyr == i) {

        STEP_3D_LINE (dxrabs, dyrabs, dcrabs, sdxr, sdyr, sdcr,

            xrr, yrr, crr, pxr, pyr, pcr);

      }

      while (pyl == i) {

        STEP_3D_LINE (dxlabs, dylabs, dclabs, sdxl, sdyl, sdcl,

            xrl, yrl, crl, pxl, pyl, pcl);

      }

      dest += stride;

    }

    PREPARE_3D_LINE (x1, y1, c1, x2, y2, c2,

        dxrabs, dyrabs, dcrabs, sdxr, sdyr, sdcr, xrr, yrr, crr, pxr, pyr, pcr);

    seg_start = y1;

    seg_end = y2;

  }

}

static void

draw_bresenham_line (guint32 * dest, gint stride,

    gint x0, gint y0, gint x1, gint y1, guint32 col)

{

  gint dx, dy;

  gint x_incr, y_incr;

  gint i, dpr, dpru, P, indep;

  dx = abs (x1 - x0);

  dy = abs (y1 - y0);

  dest = dest + y0 * stride + x0;

  x_incr = SIGN (x1 - x0);

  y_incr = SIGN (y1 - y0) * stride;

  if (dx >= dy) {

    dpr = dy << 1;

    i = dx;

    indep = x_incr;

  } else {

    dpr = dx << 1;

    i = dy;

    indep = y_incr;

  }

  dpru = dpr - (i << 1);

  P = dpr - i;

  for (; i >= 0; i--) {

    *dest = col;

    if (P > 0) {

      dest += x_incr;

      dest += y_incr;

      P += dpru;

    } else {

      dest += indep;

      P += dpr;

    }

  }

}

void

gst_smpte_paint_triangle_clock (guint32 * dest, gint stride,

    gint x0, gint y0, gint c0,

    gint x1, gint y1, gint c1, gint x2, gint y2, gint c2)

{

  gint i;

  gint sign;

  gfloat angle, angle_e;

  gfloat len1;

  angle_e = acos (((x1 - x0) * (x2 - x0) + (y1 - y0) * (y2 - y0)) /

      (sqrt ((x1 - x0) * (x1 - x0) + (y1 - y0) * (y1 - y0)) *

          sqrt ((x2 - x0) * (x2 - x0) + (y2 - y0) * (y2 - y0))));

  len1 = sqrt ((x1 - x0) * (x1 - x0) + (y1 - y0) * (y1 - y0));

  if (x1 == x2) {

    sign = SIGN (y2 - y1);

    for (i = y1; i != (y2 + sign); i += sign) {

      if (y1 == i)

        angle = 0;

      else

        angle = acos (((x1 - x0) * (x2 - x0) + (y1 - y0) * (i - y0)) /

            (len1 * sqrt ((x1 - x0) * (x1 - x0) + (i - y0) * (i -

                        y0)))) / angle_e;

      draw_bresenham_line (dest, stride,

          x0, y0, x1, i, (c2 * angle + c1 * (1.0 - angle)));

    }

  } else if (y1 == y2) {

    sign = SIGN (x2 - x1);

    for (i = x1; i != (x2 + sign); i += sign) {

      if (x1 == i)

        angle = 0;

      else

        angle = acos (((x1 - x0) * (i - x0) + (y1 - y0) * (y2 - y0)) /

            (len1 * sqrt ((i - x0) * (i - x0) + (y2 - y0) * (y2 -

                        y0)))) / angle_e;

      draw_bresenham_line (dest, stride,

          x0, y0, i, y1, (c2 * angle + c1 * (1.0 - angle)));

    }

  } else {

    g_warning ("paint triangle clock: not supported");

    return;

  }

}

void

gst_smpte_paint_box_clock (guint32 * dest, gint stride,

    gint x0, gint y0, gint c0,

    gint x1, gint y1, gint c1, gint x2, gint y2, gint c2)

{

  gfloat angle_m, col_m;

  gint xv, yv;

  if (x1 == x0) {

    xv = x2;

    yv = y1;

  } else if (y1 == y0) {

    xv = x1;

    yv = y2;

  } else {

    g_warning ("paint box clock: not supported");

    return;

  }

  angle_m = 2 * acos (((x1 - x0) * (xv - x0) + (y1 - y0) * (yv - y0)) /

      (sqrt ((x1 - x0) * (x1 - x0) + (y1 - y0) * (y1 - y0)) *

          sqrt ((xv - x0) * (xv - x0) + (yv - y0) * (yv - y0)))) / M_PI;

  col_m = c2 * angle_m + c1 * (1.0 - angle_m);

  gst_smpte_paint_triangle_clock (dest, stride,

      x0, y0, c0, x1, y1, c1, xv, yv, col_m);

  gst_smpte_paint_triangle_clock (dest, stride,

      x0, y0, c0, xv, yv, col_m, x2, y2, c2);

}