/**
 * PANDA 3D SOFTWARE
 * Copyright (c) Carnegie Mellon University.  All rights reserved.
 *
 * All use of this software is subject to the terms of the revised BSD
 * license.  You should have received a copy of this license along
 * with this source code in a file named "LICENSE."
 *
 * @file pnmPainter.I
 * @author drose
 * @date 2007-02-02
 */

/**
 *
 */
INLINE PNMPainter::
~PNMPainter() {
}

/**
 * Specifies a PNMBrush that will be used for drawing lines and edges.  If the
 * brush is a bitmap brush, its image will be smeared pixelwise along the
 * line.
 *
 * Unlike the PNMImage passed to the constructor, the PNMPainter will take
 * ownership of the pen.  It is not necessary to keep a separate pointer to
 * it.
 */
INLINE void PNMPainter::
set_pen(PNMBrush *pen) {
  _pen = pen;
}

/**
 * Returns the current pen.  See set_pen().
 */
INLINE PNMBrush *PNMPainter::
get_pen() const {
  return _pen;
}

/**
 * Specifies a PNMBrush that will be used for filling in the interiors of
 * objects.  If the brush is a bitmap brush, its image will be tiled
 * throughout the space.
 *
 * Unlike the PNMImage passed to the constructor, the PNMPainter will take
 * ownership of the fill brush.  It is not necessary to keep a separate
 * pointer to it.
 */
INLINE void PNMPainter::
set_fill(PNMBrush *fill) {
  _fill = fill;
}

/**
 * Returns the current fill brush.  See set_fill().
 */
INLINE PNMBrush *PNMPainter::
get_fill() const {
  return _fill;
}

/**
 * Draws an antialiased point on the PNMImage, using the current pen.
 */
INLINE void PNMPainter::
draw_point(float x, float y) {
  draw_line(x, y, x, y);
}

/**
 * Called within draw_line() to draw a single point of a mostly-horizontal
 * line.
 */
INLINE void PNMPainter::
draw_hline_point(int x, float xa, float ya, float xd, float yd,
                 float pixel_scale) {
  float y = (yd * (x - xa) / xd) + ya;
  int ymax = (int)cceil(y);
  int ymin = (int)cfloor(y);
  if (ymax == ymin) {
    _pen->draw(_image, x, ymin, pixel_scale);
  } else {
    _pen->draw(_image, x, ymax, (y - ymin) * pixel_scale);
    _pen->draw(_image, x, ymin, (ymax - y) * pixel_scale);
  }
}

/**
 * Called within draw_line() to draw a single point of a mostly-vertical line.
 */
INLINE void PNMPainter::
draw_vline_point(int y, float xa, float ya, float xd, float yd,
                 float pixel_scale) {
  float x = (xd * (y - ya) / yd) + xa;
  int xmax = (int)cceil(x);
  int xmin = (int)cfloor(x);
  if (xmax == xmin) {
    _pen->draw(_image, xmin, y, pixel_scale);
  } else {
    _pen->draw(_image, xmax, y, (x - xmin) * pixel_scale);
    _pen->draw(_image, xmin, y, (xmax - x) * pixel_scale);
  }
}