From 0a41b253680718040c6373b1328912f48c430ed0 Mon Sep 17 00:00:00 2001
From: Bob Polis <rpb.polis@avans.nl>
Date: Sun, 25 Oct 2020 21:55:04 +0100
Subject: [PATCH] made the animation more fancy

---
 main.cpp | 22 +++++++++++++++-------
 1 file changed, 15 insertions(+), 7 deletions(-)

diff --git a/main.cpp b/main.cpp
index 9511376..ac24167 100644
--- a/main.cpp
+++ b/main.cpp
@@ -44,6 +44,10 @@ void timer_signal_handler(int /*sig*/, siginfo_t* /*si*/, void* /*uc*/) {
 void draw() {
     static int x = 300;
     static int y = 300;
+    static int dx = 1;
+    static int dy = 1;
+    static double r = 0;
+    static double dr = 0.01;
 
     if (timer_expired) {
         timer_expired = false;
@@ -61,7 +65,7 @@ void draw() {
 
         // black rectangle
         cairo_rectangle(cr, 200, 200, 100, 100);
-        cairo_set_source_rgb(cr, 0, 0, 0);
+        cairo_set_source_rgb(cr, r, 0, 0);
         cairo_fill(cr);
 
         // dark green text
@@ -75,10 +79,14 @@ void draw() {
         main_window->show_image(*main_image);
 
         // update
-        x++;
-        y++;
-        if (x > 400) x = 300;
-        if (y > 400) y = 300;
+        x += dx;
+        y += dy;
+        if (x > 400) dx = -1;
+        if (y > 400) dy = -1;
+        if (x < 300) dx = 1;
+        if (y < 300) dy = 1;
+        r += dr;
+        if (r > 1) r = 0;
     }
 }
 
@@ -135,7 +143,7 @@ int main(int argc, const char * argv[]) {
         sev.sigev_value.sival_ptr = &timer;
         struct itimerspec ts;
         ts.it_interval.tv_sec = 0;
-        ts.it_interval.tv_nsec = 100000000;
+        ts.it_interval.tv_nsec = 25000000;
         ts.it_value.tv_sec = 0;
         ts.it_value.tv_nsec = 1;
         throw_if_min1(timer_create(CLOCK_REALTIME, &sev, &timer));
@@ -146,7 +154,7 @@ int main(int argc, const char * argv[]) {
         sc::gui::SDLImageWrapper sdl_image;
 
         // main window
-        sc::gui::Window& window {sc::gui::Window::new_window("screensaver")};
+        sc::gui::Window& window {sc::gui::Window::new_window("living art")};
         main_window = &window;
         window.add_event_handler([](const SDL_Event& event, bool quit) -> bool {
             std::cerr << "closing window " << event.window.windowID << '\n';