sway/common/background-image.c
2018-07-09 22:54:30 +01:00

120 lines
3.6 KiB
C

#include <assert.h>
#include <stdbool.h>
#include <wlr/util/log.h>
#include "background-image.h"
#include "cairo.h"
enum background_mode parse_background_mode(const char *mode) {
if (strcmp(mode, "stretch") == 0) {
return BACKGROUND_MODE_STRETCH;
} else if (strcmp(mode, "fill") == 0) {
return BACKGROUND_MODE_FILL;
} else if (strcmp(mode, "fit") == 0) {
return BACKGROUND_MODE_FIT;
} else if (strcmp(mode, "center") == 0) {
return BACKGROUND_MODE_CENTER;
} else if (strcmp(mode, "tile") == 0) {
return BACKGROUND_MODE_TILE;
} else if (strcmp(mode, "solid_color") == 0) {
return BACKGROUND_MODE_SOLID_COLOR;
}
wlr_log(WLR_ERROR, "Unsupported background mode: %s", mode);
return BACKGROUND_MODE_INVALID;
}
cairo_surface_t *load_background_image(const char *path) {
cairo_surface_t *image;
#ifdef HAVE_GDK_PIXBUF
GError *err = NULL;
GdkPixbuf *pixbuf = gdk_pixbuf_new_from_file(path, &err);
if (!pixbuf) {
wlr_log(WLR_ERROR, "Failed to load background image (%s).",
err->message);
return false;
}
image = gdk_cairo_image_surface_create_from_pixbuf(pixbuf);
g_object_unref(pixbuf);
#else
image = cairo_image_surface_create_from_png(path);
#endif //HAVE_GDK_PIXBUF
if (!image) {
wlr_log(WLR_ERROR, "Failed to read background image.");
return NULL;
}
if (cairo_surface_status(image) != CAIRO_STATUS_SUCCESS) {
wlr_log(WLR_ERROR, "Failed to read background image: %s."
#ifndef HAVE_GDK_PIXBUF
"\nSway was compiled without gdk_pixbuf support, so only"
"\nPNG images can be loaded. This is the likely cause."
#endif //HAVE_GDK_PIXBUF
, cairo_status_to_string(cairo_surface_status(image)));
return NULL;
}
return image;
}
void render_background_image(cairo_t *cairo, cairo_surface_t *image,
enum background_mode mode, int buffer_width, int buffer_height) {
double width = cairo_image_surface_get_width(image);
double height = cairo_image_surface_get_height(image);
switch (mode) {
case BACKGROUND_MODE_STRETCH:
cairo_scale(cairo,
(double)buffer_width / width,
(double)buffer_height / height);
cairo_set_source_surface(cairo, image, 0, 0);
break;
case BACKGROUND_MODE_FILL: {
double window_ratio = (double)buffer_width / buffer_height;
double bg_ratio = width / height;
if (window_ratio > bg_ratio) {
double scale = (double)buffer_width / width;
cairo_scale(cairo, scale, scale);
cairo_set_source_surface(cairo, image,
0, (double)buffer_height / 2 / scale - height / 2);
} else {
double scale = (double)buffer_height / height;
cairo_scale(cairo, scale, scale);
cairo_set_source_surface(cairo, image,
(double)buffer_width / 2 / scale - width / 2, 0);
}
break;
}
case BACKGROUND_MODE_FIT: {
double window_ratio = (double)buffer_width / buffer_height;
double bg_ratio = width / height;
if (window_ratio > bg_ratio) {
double scale = (double)buffer_height / height;
cairo_scale(cairo, scale, scale);
cairo_set_source_surface(cairo, image,
(double)buffer_width / 2 / scale - width / 2, 0);
} else {
double scale = (double)buffer_width / width;
cairo_scale(cairo, scale, scale);
cairo_set_source_surface(cairo, image,
0, (double)buffer_height / 2 / scale - height / 2);
}
break;
}
case BACKGROUND_MODE_CENTER:
cairo_set_source_surface(cairo, image,
(double)buffer_width / 2 - width / 2,
(double)buffer_height / 2 - height / 2);
break;
case BACKGROUND_MODE_TILE: {
cairo_pattern_t *pattern = cairo_pattern_create_for_surface(image);
cairo_pattern_set_extend(pattern, CAIRO_EXTEND_REPEAT);
cairo_set_source(cairo, pattern);
break;
}
case BACKGROUND_MODE_SOLID_COLOR:
case BACKGROUND_MODE_INVALID:
assert(0);
break;
}
cairo_paint(cairo);
}