nuttx/libs/libnx/nx/nx_drawcircle.c
Gregory Nutt 8a46b1f488 Squashed commit of the following:
graphics:  nx_openwindow() and nxtk_openwindow() now accept an addtional 'flag' parameter.  This argument is not used at present but will, eventually enable a RAM backed, per-window framebuffer.

    graphics/Kconfig:  Add configuration to support a rambacked framebuffer. Current marked as EXPERIMENTAL because this is a work in progress.
2019-03-13 12:34:13 -06:00

134 lines
4.6 KiB
C

/****************************************************************************
* libs/libnx/nx/nx_drawcircle.c
*
* Copyright (C) 2011, 2013, 2015 Gregory Nutt. All rights reserved.
* Author: Gregory Nutt <gnutt@nuttx.org>
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
* 3. Neither the name NuttX nor the names of its contributors may be
* used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
* COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
* OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
* AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
* ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*
****************************************************************************/
/****************************************************************************
* Included Files
****************************************************************************/
#include <nuttx/config.h>
#include <sys/types.h>
#include <debug.h>
#include <errno.h>
#include <nuttx/nx/nxglib.h>
#include <nuttx/nx/nx.h>
/****************************************************************************
* Pre-Processor Definitions
****************************************************************************/
/* Named indices into the 16 circle points generated by nxgl_circlepts */
#define POINT_0p0 0
#define POINT_22p5 1
#define POINT_45p0 2
#define POINT_67p5 3
#define POINT_90p0 4
#define POINT_112p5 5
#define POINT_135p0 6
#define POINT_157p5 7
#define POINT_180p0 8
#define POINT_202p5 9
#define POINT_225p0 10
#define POINT_247p5 11
#define POINT_270p0 12
#define POINT_292p5 13
#define POINT_315p0 14
#define POINT_337p5 15
#define NCIRCLE_POINTS 16
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* Name: nx_drawcircle
*
* Description:
* Draw a circular outline using the specified line thickness and color.
*
* Input Parameters:
* hwnd - The window handle
* center - A pointer to the point that is the center of the circle
* radius - The radius of the circle in pixels.
* width - The width of the line
* color - The color to use to fill the line
*
* Returned Value:
* OK on success; ERROR on failure with errno set appropriately
*
****************************************************************************/
int nx_drawcircle(NXWINDOW hwnd, FAR const struct nxgl_point_s *center,
nxgl_coord_t radius, nxgl_coord_t width,
nxgl_mxpixel_t color[CONFIG_NX_NPLANES])
{
struct nxgl_point_s pts[NCIRCLE_POINTS];
FAR struct nxgl_vector_s vector;
int i;
int ret;
/* Convert the circle to a set of 16 points */
nxgl_circlepts(center, radius, pts);
/* Draw each pair of points as a vector */
for (i = POINT_0p0; i < POINT_337p5; i++)
{
/* Draw one line segment */
vector.pt1.x = pts[i].x;
vector.pt1.y = pts[i].y;
vector.pt2.x = pts[i+1].x;
vector.pt2.y = pts[i+1].y;
ret = nx_drawline(hwnd, &vector, width, color, NX_LINECAP_PT1);
if (ret != OK)
{
return ret;
}
}
/* The final, closing vector is a special case */
vector.pt1.x = pts[POINT_337p5].x;
vector.pt1.y = pts[POINT_337p5].y;
vector.pt2.x = pts[POINT_0p0].x;
vector.pt2.y = pts[POINT_0p0].y;
return nx_drawline(hwnd, &vector, width, color, NX_LINECAP_PT1);
}