From a9e163b3f76aa05e4f9c45bb29d1fc061eecc9fe Mon Sep 17 00:00:00 2001
From: Taylor Bockman <tbockman@xchg.sh>
Date: Tue, 12 Nov 2019 17:28:19 -0800
Subject: [PATCH] Draw cluster means, support default 4 clusters.

---
 clusterview2/ui/mode_handlers.py |  3 ++-
 clusterview2/ui/opengl_widget.py | 54 +++++++++++++++++++++++++++++++++++++---
 main_window.py                   |  7 ++++--
 3 files changed, 58 insertions(+), 6 deletions(-)

diff --git a/clusterview2/ui/mode_handlers.py b/clusterview2/ui/mode_handlers.py
index d74dd9e..4671fb2 100644
--- a/clusterview2/ui/mode_handlers.py
+++ b/clusterview2/ui/mode_handlers.py
@@ -11,7 +11,8 @@ from clusterview2.exceptions import ExceededWindowBoundsError
 from clusterview2.mode import Mode
 from clusterview2.ui.opengl_widget import (set_drawing_event, set_move_bb_top_left,
                                            set_move_bb_bottom_right, reset_move_bbs,
-                                           viewport_height, viewport_width)
+                                           viewport_height, viewport_width,
+                                           draw_mean_circles)
 from clusterview2.point_manager import PointManager
 
 
diff --git a/clusterview2/ui/opengl_widget.py b/clusterview2/ui/opengl_widget.py
index 90fb655..1bdcc03 100644
--- a/clusterview2/ui/opengl_widget.py
+++ b/clusterview2/ui/opengl_widget.py
@@ -13,9 +13,12 @@ It should be split up into a few more separate files eventually...
 Probably even into it's own module folder.
 """
 
-from OpenGL.GL import (glBegin, glClearColor, glColor3f,
-                       glEnd, GL_LINE_LOOP, GL_POINTS,
-                       glPointSize, glVertex3f, glViewport)
+import math
+
+from OpenGL.GL import (glBegin, glClearColor, glColor3f, glColor4f,
+                       glEnable, glEnd, GL_LINE_LOOP, GL_LINE_SMOOTH,
+                       GL_POINTS, glPointSize, glVertex3f,
+                       glViewport)
 
 from clusterview2.colors import Color, COLOR_TO_RGBA
 from clusterview2.exceptions import (handle_exceptions,
@@ -188,6 +191,11 @@ def paint_gl():
 
         draw_points(PointManager.point_set)
 
+        if (__current_context.mode is Mode.CLUSTERING and
+                __current_context.clustering_solved):
+
+            draw_mean_circles(PointManager.clusters)
+
     elif __current_context.mode is Mode.MOVE:
         # We have to repeatedly draw the points while we are showing the
         # move box.
@@ -388,3 +396,43 @@ def draw_points(point_set):
                    __clamp_y(point.y),
                    0.0)                 # Z is currently fixed to 0
     glEnd()
+
+
+def draw_mean_circles(clusters: list):
+    """
+    Draws a red circle for each mean.
+
+    @param clusters The list of clusters created by k-means.
+    """
+    global __current_context
+
+    if __current_context is None:
+        raise InvalidStateError('Drawing context must be set before setting ' +
+                                'drawing mode.')
+
+    if len(clusters) == 0:
+        raise InvalidStateError('Run clustering before drawing means.')
+
+    radius = 0.02
+    segments = 100
+
+    glViewport(0, 0, __WIDTH, __HEIGHT)
+    glEnable(GL_LINE_SMOOTH)
+
+    for cluster in clusters:
+        glBegin(GL_LINE_LOOP)
+
+        blue = COLOR_TO_RGBA[Color.BLUE]
+        glColor4f(blue[0], blue[1], blue[2], 0.5)
+
+        mean = cluster.mean
+
+        x = __clamp_x(cluster.mean.x)
+        y = __clamp_y(cluster.mean.y)
+
+        for i in range(0, segments):
+            glVertex3f(x + (radius * math.cos(i * ((2 * math.pi)/segments))),
+                       y + (radius * math.sin(i * ((2 * math.pi)/segments))),
+                       0.0)
+
+        glEnd()
diff --git a/main_window.py b/main_window.py
index d641bf0..b6eb186 100644
--- a/main_window.py
+++ b/main_window.py
@@ -57,6 +57,8 @@ class MainWindow(QMainWindow, Ui_MainWindow):
         self.number_of_clusters.setMinimum(0)
         self.number_of_clusters.setMaximum(Color.count() - 2)
 
+        self.clustering_button.setEnabled(False)
+
         # We only need to set the context in our OpenGL state machine
         # wrapper once here since the window is fixed size.
         # If we allow resizing of the window, the context must be updated
@@ -84,7 +86,6 @@ class MainWindow(QMainWindow, Ui_MainWindow):
                                                            self))
 
         self.clustering_button.clicked.connect(self._clustering)
-        self.number_of_clusters.valueChanged.connect(self._clustering_enabled)
 
         self.reset_button.clicked.connect(self._reset)
 
@@ -209,7 +210,8 @@ class MainWindow(QMainWindow, Ui_MainWindow):
             refresh_point_list(self)
 
     def _clustering_enabled(self):
-        self.clustering_button.setEnabled(self.number_of_clusters.value() > 0)
+        point_count = len(list(PointManager.point_set.points))
+        self.clustering_button.setEnabled(point_count > 0)
 
     @property
     def mode(self):
@@ -260,4 +262,5 @@ class MainWindow(QMainWindow, Ui_MainWindow):
         # OpenGL event. The context passed to these functions allows
         # them to modify on screen widgets such as the QOpenGLWidget and
         # QListWidget.
+        self._clustering_enabled()
         MODE_HANDLER_MAP[self._mode](self, event)