C++基于⽮量图形库cairo绘图图形
//sudo apt-get install libcairo2-dev
//pkg-config --cflags --libs cairo
//-I/usr/include/cairo -I/usr/include/glib-2.0 -I/usr/lib/x86_64-linux-gnu/glib-2.0/include -I/usr/include/pixman-1 -I/usr/include/freetype2 -I/usr/include/libpng12  -lcairo
#include <iostream>
#include <cairo-svg.h>
#define ANGLE(ang)  (ang * 3.1415926 / 180.0)
int main(int argc, char **argv) {
cairo_t *cr;
cairo_surface_t *surface;
int cheight = 400, cwidth = cheight;
surface = (cairo_surface_t *)cairo_svg_surface_create("Cairo_example.svg", cheight, cwidth);
cr = cairo_create(surface);
cairo_pattern_t *pattern;
cairo_text_extents_t text;
int x,y;
//填充背景⿊⾊
cairo_set_source_rgb (cr, 0, 0, 0);
cairo_rectangle(cr, 0, 0, cwidth, cheight);
cairo_fill(cr);
//    cairo_set_source_rgb (cr, 0.5, 0.5, 0.5);
//    pattern = cairo_pattern_create_radial(50, 50, 5, 50, 50, 50);
/
/    cairo_pattern_add_color_stop_rgb(pattern, 0, 0.75, 0.15, 0.99);
//    cairo_pattern_add_color_stop_rgb(pattern, 0.9, 1, 1, 1);
//    cairo_set_source(cr, pattern);
//    cairo_fill(cr);
/* Writing in the foreground */
cairo_set_font_size (cr, 15);
cairo_select_font_face (cr, "Georgia", CAIRO_FONT_SLANT_NORMAL, CAIRO_FONT_WEIGHT_BOLD);
cairo_set_source_rgb (cr, 0, 0, 1);
cairo_move_to(cr, 10, 25);
cairo_show_text(cr, "你好");
cairo_move_to(cr, 10, 75);
cairo_show_text(cr, "Wikipedia!");
cairo_set_source_rgb ( cr, 0, 1, 0 );
cairo_set_antialias(cr, CAIRO_ANTIALIAS_GOOD);
cairo_set_line_width(cr, 2);
cairo_move_to(cr, 30, 10);
cairo_line_to(cr, 100, 80);
cairo_stroke(cr);
cairo_move_to(cr, 30, 10);
cairo_line_to(cr, 230, 80);
cairo_stroke(cr);
cairo_rectangle_int_t rect;
rect.x = 200;
rect.y = 200;
rect.width = 180;
rect.height = 160;
cairo_rectangle(cr, rect.x, rect.y, rect.width, rect.height);
cairo_stroke(cr);
//cairo_fill(cr);
cairo_set_source_rgba(cr, 1, 0, 1, 0.5);
cairo_set_source_rgba(cr, 1, 0, 1, 0.5);
cairo_set_line_width(cr, 15);
svg图形
int cx = 250, cy = 250, R = 130;
cairo_arc(cr, cx, cy, R, ANGLE(0), ANGLE(360));
cairo_stroke(cr);
cairo_surface_write_to_png ( surface, "demo1.png" ) ;
cairo_destroy (cr);
cairo_surface_destroy (surface);
return 0;
}
Ubuntu下的编译:
g++ `pkg-config --cflags cairo` test_cairo.cpp `pkg-config --libs cairo`注意：上⾯的符号`，不是单引号,⽽是键盘上ESC键的下⾯, !/1键的左边的按键.
运⾏结果: