src/display.c (a67d360) - libflexipix · BlinkenArea

display.c

/*
 * FlexiPix library
 *
 * Copyright 2010-2011 Stefan Schuermans <stefan schuermans info>
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, version 3 of the License.
 *
 *
 * This program 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 General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public License
 * along with this program. If not, see <http://www.gnu.org/licenses/>.
 */

#include <errno.h>
#include <stdlib.h>
#include <string.h>

#include <flexipix/display.h>
#include <flexipix/msg.h>
#include <flexipix/types.h>
#include <intern/config.h>
#include <intern/constants.h>
#include <intern/net.h>
#include <intern/types.h>

/**
 * \brief create a new FlexiPix display
 *
 * \param[in] sz_config_file name of config file to read
 * \param[in] p_msg_func message callback function or NULL
 * \param[in] p_msg_ctx user context for message callback
 * \return pointer to new FlexiPix display on success
 *         or NULL on error
 */
flp_display_t *flp_display_create(const char *sz_config_file,
                                  flp_msg_func_p_t p_msg_func,
                                  void *p_msg_ctx)
{
  flp_display_t *p_display;

/* basic display setup */

/* create display structure */
  p_display = (flp_display_t *)calloc(1, sizeof (flp_display_t));
  if (!p_display) {
    if (p_msg_func)
      p_msg_func(p_msg_ctx, flp_msg_type_err,
                 "out of memory\n");
    return NULL;
  }

/* set default bind address */
  p_display->bind_addr.sin_family = AF_INET;
  p_display->bind_addr.sin_port = htons(FLP_BIND_PORT);
  p_display->bind_addr.sin_addr.s_addr = htonl(FLP_BIND_IP);

/* no socket yet */
  p_display->sock = -1;

/* config file */

/* read config file */
  if(flp_config_proc_file(p_display, sz_config_file,
                          p_msg_func, p_msg_ctx)) {
    flp_display_free(p_display); /* cleanup everything that config file
                                    processing might heave created already */
    if (p_msg_func)
      p_msg_func(p_msg_ctx, flp_msg_type_err, "reading config file failed\n");
    return NULL;
  }

/* set up UDP socket */

/* create socket */
  p_display->sock = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
  if (!flp_sock_is_valid(p_display->sock)) {
    flp_display_free(p_display);
    if (p_msg_func) {
      char errmsg[256];
      flp_sock_get_last_error(errmsg, sizeof(errmsg));
      p_msg_func(p_msg_ctx, flp_msg_type_err,
                 "could not create UDP socket: %s\n", errmsg);
    }
    return NULL;
  }

/* bind socket */
  if (bind(p_display->sock, (struct sockaddr *)&p_display->bind_addr,
           sizeof (p_display->bind_addr))) {
    flp_display_free(p_display);
    if (p_msg_func) {
      char errmsg[256];
      flp_sock_get_last_error(errmsg, sizeof(errmsg));
      p_msg_func(p_msg_ctx, flp_msg_type_err,
                 "could not bind UDP socket to \"%s:%u\": %s\n",
                 inet_ntoa(p_display->bind_addr.sin_addr),
                 (unsigned int)ntohs(p_display->bind_addr.sin_port), errmsg);
    }
    return NULL;
  }

/* clear display */

flp_display_data_clear(p_display);

return p_display;
}

/**
 * \brief free a FlexiPix display
 *
 * \param[in] p_display pointer to FlexiPix display
 */
void flp_display_free(flp_display_t *p_display)
{
  int i;

if (p_display) {

/* free distributors */
    for (i = 0; i < FLP_DISTRI_MAX_CNT; i++) {
      if (p_display->distri_ptrs[i]) {
        flp_distri_t *p_distri = p_display->distri_ptrs[i];
        free(p_distri->p_pixels);
        free(p_distri->p_msg_buf);
        free(p_distri);
      }
    }

/* close network connection */
    if (flp_sock_is_valid(p_display->sock))
      closesocket(p_display->sock);

/* free display structutre */
    free(p_display);

} /* if (p_display) */
}

/**
 * \brief get size of display
 *
 * \param[in] p_display pointer to FlexiPix display
 * \param[out] p_width width of display
 * \param[out] p_height height of display
 */
void flp_display_get_size(flp_display_t *p_display,
                          unsigned int *p_width, unsigned int *p_height)
{
  *p_width = (unsigned int)p_display->size.x;
  *p_height = (unsigned int)p_display->size.y;
}

/**
 * \brief clear image data to output on FlexiPix display
 *
 * clears the stored image data,
 * stored image data can later be sent to the distributors using
 * flp_display_send()
 *
 * \param[in] p_display pointer to FlexiPix display
 */
void flp_display_data_clear(flp_display_t *p_display)
{
  flp_u8_t black[3] = { 0, 0, 0 };
  flp_display_data(p_display, black, 0, 0,
                   0, 0, p_display->size.x, p_display->size.y);
}

/**
 * \brief set image data to output on FlexiPix display
 *
 * updates (part of) the stored image data,
 * stored image data can later be sent to the distributors using
 * flp_display_send()
 *
 * \param[in] p_display pointer to FlexiPix display
 * \param[in] p_data pointer to rectangular section of image data,
 *                   pixels need to be in R8G8B8 format
 * \param[in] stride_x stride between two pixels in X direction
 * \param[in] stride_y stride between two pixels in Y direction
 * \param[in] x X coordinate of left side of rectangular area
 * \param[in] y Y coordinate of top side of rectangular area
 * \param[in] width with of rectangular area
 * \param[in] height height of rectangular area
 */
void flp_display_data(flp_display_t *p_display, flp_u8_t *p_data,
                      int stride_x, int stride_y,
                      unsigned int x, unsigned int y,
                      unsigned int width, unsigned int height)
{
  unsigned int distri, out, pix, i, c;
  flp_distri_t *p_distri;
  flp_u8_t *dest, *src;
  flp_pixel_t *p_pixel;
  int rx, ry;

/* set data for all distributors */
  for (distri = 0; distri < FLP_DISTRI_MAX_CNT; distri++) {
    p_distri = p_display->distri_ptrs[distri];
    if (p_distri) {

/* set pointer to start of RGB data for pixels in message buffer
         (header is already set up and stays the same) */
      dest = p_distri->p_msg_buf + FLP_MCUF_HDR_LEN;

/* get RGB data of pixels for every output */
      for (out = 0, i = 0; out < p_distri->output_cnt; out++) {
        for (pix = 0; pix < p_distri->pixel_cnt; pix++, i++) {
          p_pixel = &p_distri->p_pixels[i];

/* get pixel coordinates relative to rectangular area of image */
          rx = p_pixel->x - (int)x;
          ry = p_pixel->y - (int)y;
          /* check if pixel is within rectangular area of image */
          if (rx >= 0 && (unsigned int)rx < width
              && ry >= 0 && (unsigned int)ry < height) {
            /* get pixel data and map it */
            src = (p_data + rx * stride_x + ry * stride_y);
            for (c = 0; c < 3; c++)
              dest[c] = p_distri->mapping[c].table[src[c]];
          }

dest += 3;
        } /* for (pix ...) */
      } /* for (out ...) */

} /* if (p_distri) */
  } /* for (distri ...) */
}

/**
 * \brief send image data to distributors
 *
 * sends the currently stored image data to all configured distributors
 *
 * \param[in] p_display pointer to FlexiPix display
 */
void flp_display_send(flp_display_t *p_display)
{
  unsigned int distri;
  flp_distri_t *p_distri;
  struct sockaddr_in dest_addr;

/* send data to all distributors */
  for (distri = 0; distri < FLP_DISTRI_MAX_CNT; distri++) {
    p_distri = p_display->distri_ptrs[distri];
    if (p_distri) {

/* assemble destination address of distributor */
      dest_addr.sin_family = AF_INET;
      dest_addr.sin_port = htons(FLP_DEST_PORT);
      dest_addr.sin_addr.s_addr =
        htonl(FLP_DEST_IP_BASE + p_distri->distri * FLP_DEST_IP_STEP);

/* send message as UDP packet */
      sendto(p_display->sock, (char *)p_distri->p_msg_buf, p_distri->msg_len,
             0, (struct sockaddr *)&dest_addr, sizeof (dest_addr));

} /* if (p_distri) */
  } /* for (distri ...) */
}

libflexipix

fixed segfault if using without message callback