2 * vim:ts=4:sw=4:expandtab
4 * © 2015 Ingo Bürk and contributors (see also: LICENSE)
6 * draw.c: Utility for drawing.
13 #include <xcb/xcb_aux.h>
15 #include <cairo/cairo-xcb.h>
20 /* The default visual_type to use if none is specified when creating the surface. Must be defined globally. */
21 xcb_visualtype_t *visual_type;
23 /* Forward declarations */
24 static void draw_util_set_source_color(xcb_connection_t *conn, surface_t *surface, color_t color);
26 #define RETURN_UNLESS_SURFACE_INITIALIZED(surface) \
28 if ((surface)->id == XCB_NONE) { \
29 ELOG("Surface %p is not initialized, skipping drawing.\n", surface); \
35 * Initialize the surface to represent the given drawable.
38 void draw_util_surface_init(xcb_connection_t *conn, surface_t *surface, xcb_drawable_t drawable,
39 xcb_visualtype_t *visual, int width, int height) {
40 surface->id = drawable;
41 surface->visual_type = ((visual == NULL) ? visual_type : visual);
42 surface->width = width;
43 surface->height = height;
45 surface->gc = xcb_generate_id(conn);
46 xcb_void_cookie_t gc_cookie = xcb_create_gc_checked(conn, surface->gc, surface->id, 0, NULL);
48 xcb_generic_error_t *error = xcb_request_check(conn, gc_cookie);
50 ELOG("Could not create graphical context. Error code: %d. Please report this bug.\n", error->error_code);
54 surface->surface = cairo_xcb_surface_create(conn, surface->id, surface->visual_type, width, height);
55 surface->cr = cairo_create(surface->surface);
60 * Destroys the surface.
63 void draw_util_surface_free(xcb_connection_t *conn, surface_t *surface) {
64 xcb_free_gc(conn, surface->gc);
66 cairo_surface_destroy(surface->surface);
67 cairo_destroy(surface->cr);
69 /* We need to explicitly set these to NULL to avoid assertion errors in
70 * cairo when calling this multiple times. This can happen, for example,
71 * when setting the border of a window to none and then closing it. */
72 surface->surface = NULL;
78 * Resize the surface to the given size.
81 void draw_util_surface_set_size(surface_t *surface, int width, int height) {
82 surface->width = width;
83 surface->height = height;
85 cairo_xcb_surface_set_size(surface->surface, width, height);
90 * Parses the given color in hex format to an internal color representation.
91 * Note that the input must begin with a hash sign, e.g., "#3fbc59".
94 color_t draw_util_hex_to_color(const char *color) {
96 if (strlen(color) == strlen("#rrggbbaa")) {
100 alpha[0] = alpha[1] = 'F';
103 char groups[4][3] = {
104 {color[1], color[2], '\0'},
105 {color[3], color[4], '\0'},
106 {color[5], color[6], '\0'},
107 {alpha[0], alpha[1], '\0'}};
110 .red = strtol(groups[0], NULL, 16) / 255.0,
111 .green = strtol(groups[1], NULL, 16) / 255.0,
112 .blue = strtol(groups[2], NULL, 16) / 255.0,
113 .alpha = strtol(groups[3], NULL, 16) / 255.0,
114 .colorpixel = get_colorpixel(color)};
118 * Set the given color as the source color on the surface.
121 static void draw_util_set_source_color(xcb_connection_t *conn, surface_t *surface, color_t color) {
122 RETURN_UNLESS_SURFACE_INITIALIZED(surface);
125 cairo_set_source_rgba(surface->cr, color.red, color.green, color.blue, color.alpha);
127 uint32_t colorpixel = color.colorpixel;
128 xcb_change_gc(conn, surface->gc, XCB_GC_FOREGROUND | XCB_GC_BACKGROUND,
129 (uint32_t[]){colorpixel, colorpixel});
134 * Draw the given text using libi3.
135 * This function also marks the surface dirty which is needed if other means of
136 * drawing are used. This will be the case when using XCB to draw text.
139 void draw_util_text(i3String *text, surface_t *surface, color_t fg_color, color_t bg_color, int x, int y, int max_width) {
140 RETURN_UNLESS_SURFACE_INITIALIZED(surface);
143 /* Flush any changes before we draw the text as this might use XCB directly. */
144 CAIRO_SURFACE_FLUSH(surface->surface);
147 set_font_colors(surface->gc, fg_color, bg_color);
148 draw_text(text, surface->id, surface->gc, surface->visual_type, x, y, max_width);
151 /* Notify cairo that we (possibly) used another way to draw on the surface. */
152 cairo_surface_mark_dirty(surface->surface);
157 * Draws a filled rectangle.
158 * This function is a convenience wrapper and takes care of flushing the
159 * surface as well as restoring the cairo state.
162 void draw_util_rectangle(xcb_connection_t *conn, surface_t *surface, color_t color, double x, double y, double w, double h) {
163 RETURN_UNLESS_SURFACE_INITIALIZED(surface);
166 cairo_save(surface->cr);
168 /* Using the SOURCE operator will copy both color and alpha information directly
169 * onto the surface rather than blending it. This is a bit more efficient and
170 * allows better color control for the user when using opacity. */
171 cairo_set_operator(surface->cr, CAIRO_OPERATOR_SOURCE);
172 draw_util_set_source_color(conn, surface, color);
174 cairo_rectangle(surface->cr, x, y, w, h);
175 cairo_fill(surface->cr);
177 /* Make sure we flush the surface for any text drawing operations that could follow.
178 * Since we support drawing text via XCB, we need this. */
179 CAIRO_SURFACE_FLUSH(surface->surface);
181 cairo_restore(surface->cr);
183 draw_util_set_source_color(conn, surface, color);
185 xcb_rectangle_t rect = {x, y, w, h};
186 xcb_poly_fill_rectangle(conn, surface->id, surface->gc, 1, &rect);
191 * Clears a surface with the given color.
194 void draw_util_clear_surface(xcb_connection_t *conn, surface_t *surface, color_t color) {
195 RETURN_UNLESS_SURFACE_INITIALIZED(surface);
198 cairo_save(surface->cr);
200 /* Using the SOURCE operator will copy both color and alpha information directly
201 * onto the surface rather than blending it. This is a bit more efficient and
202 * allows better color control for the user when using opacity. */
203 cairo_set_operator(surface->cr, CAIRO_OPERATOR_SOURCE);
204 draw_util_set_source_color(conn, surface, color);
206 cairo_paint(surface->cr);
208 /* Make sure we flush the surface for any text drawing operations that could follow.
209 * Since we support drawing text via XCB, we need this. */
210 CAIRO_SURFACE_FLUSH(surface->surface);
212 cairo_restore(surface->cr);
214 draw_util_set_source_color(conn, surface, color);
216 xcb_rectangle_t rect = {0, 0, surface->width, surface->height};
217 xcb_poly_fill_rectangle(conn, surface->id, surface->gc, 1, &rect);
222 * Copies a surface onto another surface.
225 void draw_util_copy_surface(xcb_connection_t *conn, surface_t *src, surface_t *dest, double src_x, double src_y,
226 double dest_x, double dest_y, double width, double height) {
227 RETURN_UNLESS_SURFACE_INITIALIZED(src);
228 RETURN_UNLESS_SURFACE_INITIALIZED(dest);
231 cairo_save(dest->cr);
233 /* Using the SOURCE operator will copy both color and alpha information directly
234 * onto the surface rather than blending it. This is a bit more efficient and
235 * allows better color control for the user when using opacity. */
236 cairo_set_operator(dest->cr, CAIRO_OPERATOR_SOURCE);
237 cairo_set_source_surface(dest->cr, src->surface, dest_x - src_x, dest_y - src_y);
239 cairo_rectangle(dest->cr, dest_x, dest_y, width, height);
240 cairo_fill(dest->cr);
242 /* Make sure we flush the surface for any text drawing operations that could follow.
243 * Since we support drawing text via XCB, we need this. */
244 CAIRO_SURFACE_FLUSH(src->surface);
245 CAIRO_SURFACE_FLUSH(dest->surface);
247 cairo_restore(dest->cr);
249 xcb_copy_area(conn, src->id, dest->id, dest->gc, (int16_t)src_x, (int16_t)src_y,
250 (int16_t)dest_x, (int16_t)dest_y, (uint16_t)width, (uint16_t)height);