karma/flying-balls
1
1
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

Merge branch 'cairo' into faces

Browse Source
This commit is contained in:
Antonio Carzaniga 2019-07-29 18:41:23 +02:00
commit 32cd25bd56
1 changed files with 29 additions and 14 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

27
balls.c
View File

@ -39,6 +39,8 @@ unsigned int n_balls = 50;
static double g_y = 20; static double g_y = 20;
static double g_x = 0; static double g_x = 0;
static double clear_alpha = 1.0;
void random_velocity(struct ball * p) { void random_velocity(struct ball * p) {
double r2; double r2;
do { do {
@ -142,7 +144,11 @@ const char * face_filename = 0;
cairo_surface_t * face_surface = 0; cairo_surface_t * face_surface = 0;
int face_x_offset, face_y_offset; int face_x_offset, face_y_offset;
static int gravity_vector_countdown = 0;
static int gravity_vector_init = 300;
static void draw_gravity_vector() { static void draw_gravity_vector() {
if (gravity_vector_countdown != 0) {
cairo_new_path(cr); cairo_new_path(cr);
cairo_move_to(cr, width/2, height/2); cairo_move_to(cr, width/2, height/2);
cairo_line_to(cr, width/2 + g_x, height/2 + g_y); cairo_line_to(cr, width/2 + g_x, height/2 + g_y);
@ -151,6 +157,9 @@ static void draw_gravity_vector() {
cairo_stroke(cr); cairo_stroke(cr);
cairo_arc(cr, width/2 + g_x, height/2 + g_y, 3, 0, 2*M_PI); cairo_arc(cr, width/2 + g_x, height/2 + g_y, 3, 0, 2*M_PI);
cairo_fill(cr); cairo_fill(cr);
if (gravity_vector_countdown > 0)
--gravity_vector_countdown;
}
} }
static void draw_balls_onto_window () { static void draw_balls_onto_window () {
@ -158,7 +167,7 @@ static void draw_balls_onto_window () {
cr = gdk_cairo_create(window->window); cr = gdk_cairo_create(window->window);
/* clear pixmap */ /* clear pixmap */
cairo_set_source_rgba(cr, 0.0, 0.0, 0.0, 1.0); cairo_set_source_rgba(cr, 0.0, 0.0, 0.0, clear_alpha);
cairo_paint(cr); cairo_paint(cr);
draw_gravity_vector(); draw_gravity_vector();
@ -212,20 +221,23 @@ static gint keyboard_input (GtkWidget *widget, GdkEventKey *event) {
switch(event->keyval) { switch(event->keyval) {
case GDK_KEY_Up: case GDK_KEY_Up:
g_y -= 10; g_y -= 10;
gravity_vector_countdown = gravity_vector_init;
break; break;
case GDK_KEY_Down: case GDK_KEY_Down:
g_y += 10; g_y += 10;
gravity_vector_countdown = gravity_vector_init;
break; break;
case GDK_KEY_Left: case GDK_KEY_Left:
g_x -= 10; g_x -= 10;
gravity_vector_countdown = gravity_vector_init;
break; break;
case GDK_KEY_Right: case GDK_KEY_Right:
g_x += 10; g_x += 10;
gravity_vector_countdown = gravity_vector_init;
break; break;
case GDK_KEY_F: case GDK_KEY_G:
case GDK_KEY_f: case GDK_KEY_g:
g_x = rand() % 201 - 100; gravity_vector_countdown = gravity_vector_init;
g_y = rand() % 201 - 100;
break; break;
case GDK_KEY_Q: case GDK_KEY_Q:
case GDK_KEY_q: case GDK_KEY_q:
@ -259,7 +271,8 @@ void print_usage (const char * progname) {
"\tfy=<y-force>\n" "\tfy=<y-force>\n"
"\tradius=<min-radius>-<max-radius>\n" "\tradius=<min-radius>-<max-radius>\n"
"\tv=<min-velocity>-<max-velocity>\n" "\tv=<min-velocity>-<max-velocity>\n"
"\tdelta=<frame-delta-time>\n", "\tdelta=<frame-delta-time>\n"
"\tclear=<clear-alpha>\n",
progname); progname);
} }
@ -321,6 +334,8 @@ int main (int argc, const char *argv[]) {
define_face_surface(argv[i] + 5); define_face_surface(argv[i] + 5);
continue; continue;
} }
if (sscanf(argv[i], "clear=%lf", &clear_alpha) == 1)
continue;
print_usage(argv[0]); print_usage(argv[0]);
return 1; return 1;
} }