<div dir="ltr"><div class="gmail_extra"><div><div dir="ltr"><div dir="ltr"><div>ravi, </div>thanks for the information. it worked for me. </div> Thanks & Regards -- Lokesh. </div></div> <div class="gmail_quote">On Fri, Aug 8, 2014 at 11:53 AM, RAVI NANJUNDAPPA <<a href="mailto:nravi.n@samsung.com" target="_blank">nravi.n@samsung.com</a>> wrote: <blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"> hi Lokesh, I tried your sample code in my machine. I guess the program is fine except that I changed the rgb values in draw_graphlins() from <div class="">cairo_set_source_rgb( cr, 0.8, 0.8, 0.8 ); </div>to cairo_set_source_rgb( cr, 0, 0, 0 ); After this change, am able to see the grid + blue line. So, I feel it was due to rgb values which was making the grid lines not recognized by eyes. Please check this out in your environment too. Thanks and Best Regards, N Ravi ------- Original Message ------- Sender : Lokesh Chakka<<a href="mailto:lvenkatakumarchakka@gmail.com">lvenkatakumarchakka@gmail.com</a>> Date : Aug 08, 2014 10:15 (GMT+05:30) Title : [cairo] unable to get the dotted and continuous lines <div class="HOEnZb"><div class="h5"> Hello, I newly started using Cairo. I am facing one problem with the Cairo function calls. I want to first draw Cartesian grids using hyphens with gray color and after that I want to plot a normal line in blue color. I referred the program pen dashes at Basic drawing in Cairo But I am seeing only the blue color line. but not the Cartesian grids. Can some one help me by telling what mistake I am doing. #include <cairo.h> #include <gtk/gtk.h> #include <math.h> #include <inttypes.h> uint16_t drawing_width = 300, drawing_height = 200; uint16_t evaluate_y_coordinate( uint16_t y ) { return drawing_height - y; } static void draw_graphlines( cairo_t *cr ) { const uint16_t stepx = drawing_width/10, stepy = drawing_height/5; const double dashes[] = { 5, 10 }; uint32_t i; cairo_set_source_rgb( cr, 0.8, 0.8, 0.8 ); cairo_set_line_width( cr, 0.5 ); cairo_set_dash ( cr, dashes, 2, 0 ); for( i=0; i<drawing_width; i+=stepx ) {//vertical lines cairo_move_to( cr, i, evaluate_y_coordinate( 0 ) ); cairo_line_to( cr, i, evaluate_y_coordinate( drawing_height ) ); } for( i=0; i<drawing_height; i+=stepy ) {// horizontal lines cairo_move_to( cr, 0, evaluate_y_coordinate( i ) ); cairo_line_to( cr, drawing_width, evaluate_y_coordinate( i ) ); } cairo_stroke(cr); cairo_set_dash ( cr, dashes, 0, 0 ); } static void do_drawing( GtkWidget *widget, cairo_t *cr, char *data ) { GdkRGBA rgba; draw_graphlines( cr ); cairo_set_source_rgb( cr, 0, 0, 1 ); cairo_set_line_width( cr, 2.0 ); cairo_move_to( cr, 10, 10 ); cairo_line_to( cr, 100, 100 ); cairo_stroke(cr); } int main (int argc, char *argv[]) { GtkWidget *window; GtkWidget *darea; gtk_init(&argc, &argv); window = gtk_window_new(GTK_WINDOW_ TOPLEVEL); darea = gtk_drawing_area_new(); gtk_container_add(GTK_CONTAINER(window), darea); g_signal_connect(G_OBJECT(darea), "draw", G_CALLBACK(do_drawing), NULL); g_signal_connect(G_OBJECT(window), "destroy", G_CALLBACK(gtk_main_quit), NULL); gtk_window_set_position(GTK_WINDOW(window), GTK_WIN_POS_CENTER); gtk_window_set_default_size(GTK_WINDOW(window), drawing_width, drawing_height ); gtk_window_set_title(GTK_WINDOW(window), "Fill & stroke"); gtk_widget_show_all(window); gtk_main(); return 0; } Thanks & Regards -- Lokesh</div></div></blockquote></div> </div></div>