diff options
Diffstat (limited to 'xcb_fixed.c')
| -rw-r--r-- | xcb_fixed.c | 211 |
1 files changed, 211 insertions, 0 deletions
diff --git a/xcb_fixed.c b/xcb_fixed.c new file mode 100644 index 0000000..b230b78 --- /dev/null +++ b/xcb_fixed.c @@ -0,0 +1,211 @@ +/* XCB application drawing an updating bitmap in a window +* +* Inspired by the xcb black rectangle in a window example +* +* Copyright 2010 V. R. Sanders, released under the MIT licence +*/ + +/* compile with: +* gcc -Wall -lxcb-icccm -lxcb -lxcb-image -o disp disp.c +*/ + +#include <string.h> + +#include <xcb/xcb.h> +#include <xcb/xcb_image.h> +#include <xcb/xcb_atom.h> +#include <xcb/xcb_icccm.h> +#include <stdio.h> +#include <stdlib.h> +#include <sys/types.h> + +static xcb_format_t * +find_format (xcb_connection_t * c, uint8_t depth, uint8_t bpp) +{ + const xcb_setup_t *setup = xcb_get_setup(c); + xcb_format_t *fmt = xcb_setup_pixmap_formats(setup); + xcb_format_t *fmtend = fmt + xcb_setup_pixmap_formats_length(setup); + for(; fmt != fmtend; ++fmt) + if((fmt->depth == depth) && (fmt->bits_per_pixel == bpp)) { + /* printf("fmt %p has pad %d depth %d, bpp %d\n", + fmt,fmt->scanline_pad, depth,bpp); */ + return fmt; + } + return 0; +} + +void +fillimage(unsigned char *p, int width, int height) +{ + int i, j; + for(j=0; j < height; j++) + { + for(i=0; i < width; i++) + { + if((i < 256)&&(j < 256)) + { + *p++=rand()%256; // blue + *p++=rand()%256; // green + *p++=rand()%256; // red + } else { + *p++=i%256; // blue + *p++=j%256; // green + if(i < 256) + *p++=i%256; // red + else if(j < 256) + *p++=j%256; // red + else + *p++=(256-j)%256; // red + } + p++; /* unused byte */ + } + } +} + +xcb_image_t * +CreateTrueColorImage(xcb_connection_t *c, + int width, + int height) +{ + const xcb_setup_t *setup = xcb_get_setup(c); + unsigned char *image32=(unsigned char *)malloc(width*height*4); + xcb_format_t *fmt = find_format(c, 24, 32); + if (fmt == NULL) + return NULL; + + fillimage(image32, width, height); + + return xcb_image_create(width, + height, + XCB_IMAGE_FORMAT_Z_PIXMAP, + fmt->scanline_pad, + fmt->depth, + fmt->bits_per_pixel, + 0, + setup->image_byte_order, + XCB_IMAGE_ORDER_LSB_FIRST, + image32, + width*height*4, + image32); +} + +int +main (int argc, char **argv) +{ + xcb_connection_t *c; + xcb_screen_t *s; + xcb_window_t w; + xcb_pixmap_t pmap; + xcb_gcontext_t gc; + xcb_generic_event_t *e; + uint32_t mask; + uint32_t values[2]; + int done=0; + xcb_image_t *image; + uint8_t *image32; + xcb_expose_event_t *ee; + char *title="Hello World!"; + xcb_size_hints_t *hints; + + /* open connection with the server */ + c = xcb_connect (NULL, NULL); + + if (!c) { + printf ("Cannot open display\n"); + exit (1); + } + + s = xcb_setup_roots_iterator (xcb_get_setup (c)).data; + + /* printf("root depth %d\n",s->root_depth); */ + + /* create image */ + image = CreateTrueColorImage(c, 640, 480); + if (image == NULL) { + printf ("Cannot create iamge\n"); + xcb_disconnect(c); + return 1; + } + image32 = image->data; + + /* create window */ + mask = XCB_CW_BACK_PIXEL | XCB_CW_EVENT_MASK; + values[0] = s->white_pixel; + values[1] = XCB_EVENT_MASK_EXPOSURE | + XCB_EVENT_MASK_KEY_PRESS | + XCB_EVENT_MASK_BUTTON_PRESS; + + w = xcb_generate_id (c); + xcb_create_window (c, XCB_COPY_FROM_PARENT, w, s->root, + 10, 10, image->width, image->height, 1, + XCB_WINDOW_CLASS_INPUT_OUTPUT, + s->root_visual, + mask, values); + + /*[> set size hits on window <]*/ + /*hints = xcb_alloc_size_hints();*/ + /*xcb_size_hints_set_max_size(hints, image->width,image->height);*/ + /*xcb_size_hints_set_min_size(hints, image->width,image->height);*/ + /*xcb_set_wm_size_hints(c, w, WM_NORMAL_HINTS, hints);*/ + + /* create backing pixmap */ + pmap = xcb_generate_id(c); + xcb_create_pixmap(c, 24, pmap, w, image->width, image->height); + + /* create pixmap plot gc */ + mask = XCB_GC_FOREGROUND | XCB_GC_BACKGROUND; + values[0] = s->black_pixel; + values[1] = 0xffffff; + + gc = xcb_generate_id (c); + xcb_create_gc (c, gc, pmap, mask, values); + + /* put the image into the pixmap */ + xcb_image_put(c, pmap, gc, image, 0, 0, 0); + + /* show the window */ + xcb_map_window (c, w); + xcb_flush (c); + + /* event loop */ + while (!done && (e = xcb_wait_for_event (c))) { + switch (e->response_type) { + case XCB_EXPOSE: + ee=(xcb_expose_event_t *)e; + /* printf ("expose %d,%d - %d,%d\n", + ee->x,ee->y,ee->width,ee->height); */ + xcb_copy_area(c, pmap, w, gc, + ee->x, + ee->y, + ee->x, + ee->y, + ee->width, + ee->height); + xcb_flush (c); + image32+=16; + break; + + /*case XCB_KEY_PRESS:*/ + /*[> exit on keypress <]*/ + /*done = 1;*/ + /*break;*/ + + case XCB_BUTTON_PRESS: + fillimage(image->data, image->width, image->height); + memset(image->data, 0, image32 - image->data); + xcb_image_put(c, pmap, gc, image, 0, 0, 0); + xcb_copy_area(c, pmap, w, gc, 0,0,0,0,image->width,image->height); + xcb_flush (c); + break; + } + free (e); + } + + /* free pixmap */ + xcb_free_pixmap(c, pmap); + + /* close connection to server */ + xcb_disconnect (c); + + return 0; +} |