From 4154624aa3b43ffe3647436d81088a5a9a2b6f0c Mon Sep 17 00:00:00 2001
From: Bob Polis <rpb.polis@avans.nl>
Date: Mon, 16 Nov 2020 12:28:39 +0100
Subject: [PATCH] added function to construct a rounded rect

---
 src/ScreensaverPlugin.cpp | 20 ++++++++++++++++++++
 src/ScreensaverPlugin.hpp |  1 +
 2 files changed, 21 insertions(+)

diff --git a/src/ScreensaverPlugin.cpp b/src/ScreensaverPlugin.cpp
index 4b17fe9..ca204cc 100644
--- a/src/ScreensaverPlugin.cpp
+++ b/src/ScreensaverPlugin.cpp
@@ -73,3 +73,23 @@ double ScreensaverPlugin::random_between(double v1, double v2) {
     std::uniform_real_distribution<double> dist {v1, v2};
     return dist(_eng);
 }
+
+void ScreensaverPlugin::rounded_rect(const cairo_rectangle_t& rect, double radius) {
+    double x0 = rect.x;
+    double x1 = rect.x + radius;
+    double x3 = rect.x + rect.width;
+    double x2 = x3 - radius;
+    double y0 = rect.y;
+    double y3 = rect.y + rect.height;
+    double y1 = rect.y + radius;
+    double y2 = y3 - radius;
+    cairo_move_to(_c, x1, y0);
+    cairo_line_to(_c, x2, y0);
+    cairo_arc(_c, x2, y1, radius, 1.5 * M_PI, 0);
+    cairo_line_to(_c, x3, y2);
+    cairo_arc(_c, x2, y2, radius, 0, 0.5 * M_PI);
+    cairo_line_to(_c, x1, y3);
+    cairo_arc(_c, x1, y2, radius, 0.5 * M_PI, M_PI);
+    cairo_line_to(_c, x0, y1);
+    cairo_arc(_c, x1, y1, radius, M_PI, 1.5 * M_PI);
+}
diff --git a/src/ScreensaverPlugin.hpp b/src/ScreensaverPlugin.hpp
index 84a67ee..2ff05bb 100644
--- a/src/ScreensaverPlugin.hpp
+++ b/src/ScreensaverPlugin.hpp
@@ -36,6 +36,7 @@ class ScreensaverPlugin {
         double random_y();
         double random01();
         double random_between(double v1, double v2);
+        void rounded_rect(const cairo_rectangle_t& rect, double radius);
 };
 
 #endif // _ScreensaverPlugin_H_