/*
* vim:ts=4:sw=4:expandtab
*
* © 2015 Ingo Bürk and contributors (see also: LICENSE)
*
* draw.c: Utility for drawing.
*
*/
#include "libi3.h"
#include <stdlib.h>
#include <string.h>
#include <xcb/xcb.h>
#include <xcb/xcb_aux.h>
/* The default visual_type to use if none is specified when creating the surface. Must be defined globally. */
extern xcb_visualtype_t *visual_type;
/* Forward declarations */
static void draw_util_set_source_color(surface_t *surface, color_t color);
#define RETURN_UNLESS_SURFACE_INITIALIZED(surface) \
do { \
if ((surface)->id == XCB_NONE) { \
ELOG("Surface %p is not initialized, skipping drawing.\n", surface); \
return; \
} \
} while (0)
/*
* Initialize the surface to represent the given drawable.
*
*/
void draw_util_surface_init(xcb_connection_t *conn, surface_t *surface, xcb_drawable_t drawable,
xcb_visualtype_t *visual, int width, int height) {
surface->id = drawable;
surface->width = width;
surface->height = height;
if (visual == NULL)
visual = visual_type;
surface->gc = xcb_generate_id(conn);
xcb_void_cookie_t gc_cookie = xcb_create_gc_checked(conn, surface->gc, surface->id, 0, NULL);
xcb_generic_error_t *error = xcb_request_check(conn, gc_cookie);
if (error != NULL) {
ELOG("Could not create graphical context. Error code: %d. Please report this bug.\n", error->error_code);
free(error);
}
surface->surface = cairo_xcb_surface_create(conn, surface->id, visual, width, height);
surface->cr = cairo_create(surface->surface);
}
/*
* Destroys the surface.
*
*/
void draw_util_surface_free(xcb_connection_t *conn, surface_t *surface) {
cairo_status_t status = CAIRO_STATUS_SUCCESS;
if (surface->cr) {
status = cairo_status(surface->cr);
}
if (status != CAIRO_STATUS_SUCCESS) {
LOG("Found cairo context in an error status while freeing, error %d is %s",
status, cairo_status_to_string(status));
}
/* NOTE: This function is also called on uninitialised surface_t instances.
* The x11 error from xcb_free_gc(conn, XCB_NONE) is silently ignored
* elsewhere.
*/
xcb_free_gc(conn, surface->gc);
cairo_surface_destroy(surface->surface);
cairo_destroy(surface->cr);
/* We need to explicitly set these to NULL to avoid assertion errors in
* cairo when calling this multiple times. This can happen, for example,
* when setting the border of a window to none and then closing it. */
surface->surface = NULL;
surface->cr = NULL;
}
/*
* Resize the surface to the given size.
*
*/
void draw_util_surface_set_size(surface_t *surface, int width, int height) {
surface->width = width;
surface->height = height;
cairo_xcb_surface_set_size(surface->surface, width, height);
}
/*
* Parses the given color in hex format to an internal color representation.
* Note that the input must begin with a hash sign, e.g., "#3fbc59".
*
*/
color_t draw_util_hex_to_color(const char *color) {
if (strlen(color) < 6 || color[0] != '#') {
ELOG("Could not parse color: %s\n", color);
return draw_util_hex_to_color("#A9A9A9");
}
char alpha[2];
if (strlen(color) == strlen("#rrggbbaa")) {
alpha[0] = color[7];
alpha[1] = color[8];
} else {
alpha[0] = alpha[1] = 'F';
}
char groups[4][3] = {
{color[1], color[2], '\0'},
{color[3], color[4], '\0'},
{color[5], color[6], '\0'},
{alpha[0], alpha[1], '\0'}};
return (color_t){
.red = strtol(groups[0], NULL, 16) / 255.0,
.green = strtol(groups[1], NULL, 16) / 255.0,
.blue = strtol(groups[2], NULL, 16) / 255.0,
.alpha = strtol(groups[3], NULL, 16) / 255.0,
.colorpixel = get_colorpixel(color)};
}
/*
* Set the given color as the source color on the surface.
*
*/
static void draw_util_set_source_color(surface_t *surface, color_t color) {
RETURN_UNLESS_SURFACE_INITIALIZED(surface);
cairo_set_source_rgba(surface->cr, color.red, color.green, color.blue, color.alpha);
}
/*
* Draw the given text using libi3.
* This function also marks the surface dirty which is needed if other means of
* drawing are used. This will be the case when using XCB to draw text.
*
*/
void draw_util_text(i3String *text, surface_t *surface, color_t fg_color, color_t bg_color, int x, int y, int max_width) {
RETURN_UNLESS_SURFACE_INITIALIZED(surface);
/* Flush any changes before we draw the text as this might use XCB directly. */
CAIRO_SURFACE_FLUSH(surface->surface);
set_font_colors(surface->gc, fg_color, bg_color);
draw_text(text, surface->id, surface->gc, surface->surface, x, y, max_width);
/* Notify cairo that we (possibly) used another way to draw on the surface. */
cairo_surface_mark_dirty(surface->surface);
}
/**
* Draw the given image using libi3.
* This function is a convenience wrapper and takes care of flushing the
* surface as well as restoring the cairo state.
*
*/
void draw_util_image(cairo_surface_t *image, surface_t *surface, int x, int y, int width, int height) {
RETURN_UNLESS_SURFACE_INITIALIZED(surface);
cairo_save(surface->cr);
cairo_translate(surface->cr, x, y);
const int src_width = cairo_image_surface_get_width(image);
const int src_height = cairo_image_surface_get_height(image);
double scale = MIN((double)width / src_width, (double)height / src_height);
cairo_scale(surface->cr, scale, scale);
cairo_set_source_surface(surface->cr, image, 0, 0);
cairo_paint(surface->cr);
cairo_restore(surface->cr);
}
/*
* Draws a filled rectangle.
* This function is a convenience wrapper and takes care of flushing the
* surface as well as restoring the cairo state.
*
*/
void draw_util_rectangle(surface_t *surface, color_t color, double x, double y, double w, double h) {
RETURN_UNLESS_SURFACE_INITIALIZED(surface);
cairo_save(surface->cr);
/* Using the SOURCE operator will copy both color and alpha information directly
* onto the surface rather than blending it. This is a bit more efficient and
* allows better color control for the user when using opacity. */
cairo_set_operator(surface->cr, CAIRO_OPERATOR_SOURCE);
draw_util_set_source_color(surface, color);
cairo_rectangle(surface->cr, x, y, w, h);
cairo_fill(surface->cr);
/* Make sure we flush the surface for any text drawing operations that could follow.
* Since we support drawing text via XCB, we need this. */
CAIRO_SURFACE_FLUSH(surface->surface);
cairo_restore(surface->cr);
}
/*
* Clears a surface with the given color.
*
*/
void draw_util_clear_surface(surface_t *surface, color_t color) {
RETURN_UNLESS_SURFACE_INITIALIZED(surface);
cairo_save(surface->cr);
/* Using the SOURCE operator will copy both color and alpha information directly
* onto the surface rather than blending it. This is a bit more efficient and
* allows better color control for the user when using opacity. */
cairo_set_operator(surface->cr, CAIRO_OPERATOR_SOURCE);
draw_util_set_source_color(surface, color);
cairo_paint(surface->cr);
/* Make sure we flush the surface for any text drawing operations that could follow.
* Since we support drawing text via XCB, we need this. */
CAIRO_SURFACE_FLUSH(surface->surface);
cairo_restore(surface->cr);
}
/*
* Copies a surface onto another surface.
*
*/
void draw_util_copy_surface(surface_t *src, surface_t *dest, double src_x, double src_y,
double dest_x, double dest_y, double width, double height) {
RETURN_UNLESS_SURFACE_INITIALIZED(src);
RETURN_UNLESS_SURFACE_INITIALIZED(dest);
cairo_save(dest->cr);
/* Using the SOURCE operator will copy both color and alpha information directly
* onto the surface rather than blending it. This is a bit more efficient and
* allows better color control for the user when using opacity. */
cairo_set_operator(dest->cr, CAIRO_OPERATOR_SOURCE);
cairo_set_source_surface(dest->cr, src->surface, dest_x - src_x, dest_y - src_y);
cairo_rectangle(dest->cr, dest_x, dest_y, width, height);
cairo_fill(dest->cr);
/* Make sure we flush the surface for any text drawing operations that could follow.
* Since we support drawing text via XCB, we need this. */
CAIRO_SURFACE_FLUSH(src->surface);
CAIRO_SURFACE_FLUSH(dest->surface);
cairo_restore(dest->cr);
}