{"id":2602,"date":"2010-08-21T23:33:20","date_gmt":"2010-08-21T18:03:20","guid":{"rendered":"http:\/\/www.jeffrin.in\/?p=2602"},"modified":"2010-08-21T23:33:20","modified_gmt":"2010-08-21T18:03:20","slug":"cairo-graphics-0-9-intersection-ii","status":"publish","type":"post","link":"https:\/\/www.trueangle.org\/index.php\/2010\/08\/21\/cairo-graphics-0-9-intersection-ii\/","title":{"rendered":"cairo graphics 0.9 intersection II"},"content":{"rendered":"

\"\"<\/a>
\n
\n\/* Jeffrin Jose Licensed GPL v3 Copyright
\nAugust 2010 GPL --> http:\/\/www.gnu.org\/copyleft\/gpl.html *\/
\n\/\/ module do_draw<\/p>\n

\/\/do_draw will be executed in a separate thread whenever we would like to update
\n\/\/our animation
\nvoid *do_draw(void *ptr){<\/p>\n

currently_drawing = 1;<\/p>\n

int width, height;
\n gdk_threads_enter();
\n gdk_drawable_get_size(pixmap, &width, &height);
\n gdk_threads_leave();<\/p>\n

\/\/create a gtk-independant surface to draw on
\n cairo_surface_t *cst = cairo_image_surface_create(CAIRO_FORMAT_ARGB32, width, height);
\n cairo_t *cr = cairo_create(cst);<\/p>\n

\/\/Vertical Line
\n cairo_move_to(cr, 200,30);
\n cairo_line_to(cr,200,200);<\/p>\n

\/\/Horizontal Line
\n cairo_move_to(cr, 50,120);
\n cairo_line_to(cr,350,120);<\/p>\n

\/\/do some time-consuming drawing
\n static int i = 0;
\n ++i; i = i % 300; \/\/give a little movement to our animation
\n cairo_set_source_rgb (cr, .9, .9, .9);
\n cairo_paint(cr);
\n cairo_set_source_rgb (cr, 0.8, 0.5, 0.9);
\n cairo_move_to(cr, 50,50);
\n int j,k;
\n\/* for(k=0; k<100; ++k){*\/ \/\/lets just redraw lots of times to use a lot of proc power
\n for(j=0; j < 100; j++){
\n cairo_set_source_rgb (cr, 0.8, 0.5, 0.9);
\n cairo_move_to(cr, 100,76);
\n \/* cairo_line_to(cr,200+i,100);*\/
\n\/* cairo_arc(cr,300+i,100,4,0, 2*M_PI);*\/
\n\/* cairo_arc(cr,70+i,100,40,0,2*M_PI);*\/
\n if ( i < 100)
\n cairo_arc(cr, 100+i,76,0,0,0);
\n \/* cairo_rectangle(cr,50+i,50+i,50,50); *\/<\/p>\n

cairo_stroke(cr);
\n }
\n \/* }*\/
\n cairo_destroy(cr);
\n \/\/When dealing with gdkPixmap's, we need to make sure not to
\n \/\/access them from outside gtk_main().
\n gdk_threads_enter();<\/p>\n

cairo_t *cr_pixmap = gdk_cairo_create(pixmap);
\n cairo_set_source_surface (cr_pixmap, cst, 0, 0);
\n cairo_paint(cr_pixmap);
\n cairo_destroy(cr_pixmap);<\/p>\n

gdk_threads_leave();<\/p>\n

cairo_surface_destroy(cst);<\/p>\n

currently_drawing = 0;<\/p>\n

return NULL;
\n}
\n<\/code><\/p>\n","protected":false},"excerpt":{"rendered":"

\/* Jeffrin Jose Licensed GPL v3 Copyright August 2010 GPL –> http:\/\/www.gnu.org\/copyleft\/gpl.html *\/ \/\/ module do_draw \/\/do_draw will be executed in a separate thread whenever we would like to update \/\/our animation void *do_draw(void *ptr){ currently_drawing = 1; int width, height; gdk_threads_enter(); gdk_drawable_get_size(pixmap, &width, &height); gdk_threads_leave(); \/\/create a gtk-independant surface to draw on cairo_surface_t *cst … <\/p>\n

Continue reading “cairo graphics 0.9 intersection II”<\/span><\/a><\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":[],"categories":[1],"tags":[965,1022,1120,1357],"_links":{"self":[{"href":"https:\/\/www.trueangle.org\/index.php\/wp-json\/wp\/v2\/posts\/2602"}],"collection":[{"href":"https:\/\/www.trueangle.org\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.trueangle.org\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.trueangle.org\/index.php\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.trueangle.org\/index.php\/wp-json\/wp\/v2\/comments?post=2602"}],"version-history":[{"count":0,"href":"https:\/\/www.trueangle.org\/index.php\/wp-json\/wp\/v2\/posts\/2602\/revisions"}],"wp:attachment":[{"href":"https:\/\/www.trueangle.org\/index.php\/wp-json\/wp\/v2\/media?parent=2602"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.trueangle.org\/index.php\/wp-json\/wp\/v2\/categories?post=2602"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.trueangle.org\/index.php\/wp-json\/wp\/v2\/tags?post=2602"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}