From a96083c7d156f21ab4b347c7a145bd3b0213d1b0 Mon Sep 17 00:00:00 2001
From: diegohce <diego.cena@gmail.com>
Date: Wed, 14 Aug 2024 14:47:56 -0300
Subject: [PATCH] added window pollkey function

---
 highgui.cpp     |  4 ++++
 highgui.go      | 19 +++++++++++++++++++
 highgui_gocv.h  |  1 +
 highgui_test.go | 11 +++++++++++
 4 files changed, 35 insertions(+)

diff --git a/highgui.cpp b/highgui.cpp
index 87177131..0e0c812b 100644
--- a/highgui.cpp
+++ b/highgui.cpp
@@ -29,6 +29,10 @@ int Window_WaitKey(int delay = 0) {
     return cv::waitKey(delay);
 }
 
+int Window_PollKey(void) {
+    return cv::pollKey();
+}
+
 void Window_Move(const char* winname, int x, int y) {
     cv::moveWindow(winname, x, y);
 }
diff --git a/highgui.go b/highgui.go
index a32e1cd9..b3e4245d 100644
--- a/highgui.go
+++ b/highgui.go
@@ -162,6 +162,25 @@ func (w *Window) WaitKey(delay int) int {
 	return int(C.Window_WaitKey(C.int(delay)))
 }
 
+// PollKey polls for a pressed key.
+// The function pollKey polls for a key event without waiting.
+// It returns the code of the pressed key or -1 if no key was pressed since
+// the last invocation. To wait until a key was pressed, use waitKey.
+//
+// The functions waitKey and pollKey are the only methods in HighGUI that can
+// fetch and handle GUI events, so one of them needs to be called periodically
+// for normal event processing unless HighGUI is used within an environment that
+// takes care of event processing.
+// The function only works if there is at least one HighGUI window created and
+// the window is active. If there are several HighGUI windows, any of them can
+// be active.
+//
+// For further details, please see:
+// https://docs.opencv.org/4.x/d7/dfc/group__highgui.html#ga6d20fbd3100ec3badc1eaa653aff99d7
+func (w *Window) PollKey() int {
+	return int(C.Window_PollKey())
+}
+
 // MoveWindow moves window to the specified position.
 //
 // For further details, please see:
diff --git a/highgui_gocv.h b/highgui_gocv.h
index d1bd33b5..6a12e86e 100644
--- a/highgui_gocv.h
+++ b/highgui_gocv.h
@@ -16,6 +16,7 @@ double Window_GetProperty(const char* winname, int flag);
 void Window_SetProperty(const char* winname, int flag, double value);
 void Window_SetTitle(const char* winname, const char* title);
 int Window_WaitKey(int);
+int Window_PollKey(void);
 void Window_Move(const char* winname, int x, int y);
 void Window_Resize(const char* winname, int width, int height);
 struct Rect Window_SelectROI(const char* winname, Mat img);
diff --git a/highgui_test.go b/highgui_test.go
index bb69dd7e..a5f3554b 100644
--- a/highgui_test.go
+++ b/highgui_test.go
@@ -112,3 +112,14 @@ func TestTrackbarWithValue(t *testing.T) {
 		t.Error("Trackbar pos should have been 50")
 	}
 }
+
+func TestPollKey(t *testing.T) {
+
+	w := NewWindow("polly")
+	defer w.Close()
+
+	if v := w.PollKey(); v != -1 {
+		t.Errorf("got %d want -1", v)
+	}
+
+}