114 lines
2.7 KiB
C
114 lines
2.7 KiB
C
/*
|
|
* fbdash.c
|
|
*
|
|
* Adapted by Florian Klemenz for use in the fb_dash project
|
|
*
|
|
* Source and all credit goes to
|
|
* http://raspberrycompote.blogspot.ie/2014/03/low-level-graphics-on-raspberry-pi-part_14.html
|
|
*
|
|
* Original work by J-P Rosti (a.k.a -rst- and 'Raspberry Compote')
|
|
*
|
|
* Licensed under the Creative Commons Attribution 3.0 Unported License
|
|
* (http://creativecommons.org/licenses/by/3.0/deed.en_US)
|
|
*
|
|
* Distributed in the hope that this will be useful,
|
|
* but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
|
|
*
|
|
*/
|
|
|
|
#include "fblib.h"
|
|
|
|
// 'global' variables to store screen info
|
|
char *fbp = 0;
|
|
struct fb_var_screeninfo vinfo;
|
|
struct fb_fix_screeninfo finfo;
|
|
|
|
|
|
// helper function for drawing - no more need to go mess with
|
|
// the main function when just want to change what to draw...
|
|
void draw() {
|
|
|
|
clear_screen(fbp);
|
|
|
|
// horizontal spacersint x_space = 10;
|
|
int y_step_width = vinfo.yres / 4;
|
|
for (int i = 1; i < 4; i++) {
|
|
int x0 = 15;
|
|
int x1 = vinfo.xres - x0;
|
|
int y = y_step_width * i;
|
|
|
|
int r = 200;
|
|
int g = 32;
|
|
int b = 32;
|
|
|
|
draw_line(fbp, x0, y-1, x1, y-1, r, g, b);
|
|
draw_line(fbp, x0, y , x1, y , r, g, b);
|
|
draw_line(fbp, x0, y+1, x1, y+1, r, g, b);
|
|
}
|
|
|
|
|
|
|
|
|
|
|
|
|
|
}
|
|
|
|
// application entry point
|
|
int main(int argc, char* argv[])
|
|
{
|
|
|
|
int fbfd = 0;
|
|
//struct fb_var_screeninfo orig_vinfo;
|
|
long int screensize = 0;
|
|
|
|
// Open the framebuffer file for reading and writing
|
|
fbfd = open("/dev/fb1", O_RDWR);
|
|
if (fbfd == -1) {
|
|
printf("Error: cannot open framebuffer device.\n");
|
|
return(1);
|
|
}
|
|
printf("The framebuffer device was opened successfully.\n");
|
|
|
|
// Get variable screen information
|
|
if (ioctl(fbfd, FBIOGET_VSCREENINFO, &vinfo)) {
|
|
printf("Error reading variable information.\n");
|
|
}
|
|
printf("Variable info: %dx%d, %dbpp\n",
|
|
vinfo.xres, vinfo.yres,
|
|
vinfo.bits_per_pixel );
|
|
|
|
// Get fixed screen information
|
|
if (ioctl(fbfd, FBIOGET_FSCREENINFO, &finfo)) {
|
|
printf("Error reading fixed information.\n");
|
|
}
|
|
printf("Fixed info: smem_len %d, line_length %d\n", finfo.smem_len, finfo.line_length);
|
|
|
|
// map fb to user mem
|
|
screensize = finfo.smem_len;
|
|
fbp = (char*)mmap(0,
|
|
screensize,
|
|
PROT_READ | PROT_WRITE,
|
|
MAP_SHARED,
|
|
fbfd,
|
|
0);
|
|
|
|
if ((int)fbp == -1) {
|
|
printf("Failed to mmap.\n");
|
|
}
|
|
else {
|
|
// draw...
|
|
draw();
|
|
}
|
|
|
|
// cleanup
|
|
//clear_screen(fbp);
|
|
// unmap fb file from memory
|
|
munmap(fbp, screensize);
|
|
// close fb file
|
|
close(fbfd);
|
|
|
|
return 0;
|
|
|
|
}
|