incubator-nuttx/libs/libnx/nx/nx_drawline.c

145 lines
4.2 KiB
C

/****************************************************************************
* libs/libnx/nx/nx_drawline.c
*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership. The
* ASF licenses this file to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance with the
* License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
* WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
* License for the specific language governing permissions and limitations
* under the License.
*
****************************************************************************/
/****************************************************************************
* 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>
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* Name: nx_drawline
*
* Description:
* Fill the specified line in the window with the specified color. This
* is simply a wrapper that uses nxgl_splitline() to break the line into
* trapezoids and then calls nx_filltrapezoid() to render the line.
*
* Input Parameters:
* hwnd - The window handle
* vector - Describes the line to be drawn
* width - The width of the line
* color - The color to use to fill the line
* caps - Draw a circular cap on the ends of the line to support better
* line joins
*
* Returned Value:
* OK on success; ERROR on failure with errno set appropriately
*
****************************************************************************/
int nx_drawline(NXWINDOW hwnd, FAR struct nxgl_vector_s *vector,
nxgl_coord_t width, nxgl_mxpixel_t color[CONFIG_NX_NPLANES],
uint8_t caps)
{
struct nxgl_trapezoid_s trap[3];
struct nxgl_rect_s rect;
int ret;
#ifdef CONFIG_DEBUG_FEATURES
if (hwnd == NULL || vector == NULL || width < 1 || color == NULL)
{
set_errno(EINVAL);
return ERROR;
}
#endif
/* Split the line into trapezoids */
ret = nxgl_splitline(vector, trap, &rect, width);
switch (ret)
{
/* 0: Line successfully broken up into three trapezoids. Values in
* traps[0], traps[1], and traps[2] are valid.
*/
case 0:
ret = nx_filltrapezoid(hwnd, NULL, &trap[0], color);
if (ret == OK)
{
ret = nx_filltrapezoid(hwnd, NULL, &trap[1], color);
if (ret == OK)
{
ret = nx_filltrapezoid(hwnd, NULL, &trap[2], color);
}
}
break;
/* 1: Line successfully represented by one trapezoid. Value in traps[1]
* is valid.
*/
case 1:
ret = nx_filltrapezoid(hwnd, NULL, &trap[1], color);
break;
/* 2: Line successfully represented by one rectangle. Value in rect is
* valid
*/
case 2:
ret = nx_fill(hwnd, &rect, color);
break;
/* <0: On errors, a negated errno value is returned. */
default:
set_errno(-ret);
return ERROR;
}
/* Draw circular caps at each end of the line to support better line
* joins
*/
if (caps != NX_LINECAP_NONE && width >= 3)
{
nxgl_coord_t radius = width >> 1;
/* Draw a circle at pt1 */
ret = OK;
if ((caps & NX_LINECAP_PT1) != 0)
{
ret = nx_fillcircle(hwnd, &vector->pt1, radius, color);
}
/* Draw a circle at pt2 */
if (ret == OK && (caps & NX_LINECAP_PT2) != 0)
{
ret = nx_fillcircle(hwnd, &vector->pt2, radius, color);
}
}
return ret;
}