Простой поддон для цветов

Question

Попытка сделать палитру рисования похожей на туториал и редактировать ее

и ошибка с selectedColour;, она должна содержать выбранный цвет из массива struct color и способ запуска в функции init для запуска кода

#include <GL\glew.h>
#include <GL\freeglut.h>

class ColourPalette {
struct Colour {
 float r, g, b;
};
public:

// Array of colours in the palette
static const Colour colours[];
static const Colour selectedColour;
// index of selected colour in above array
static int selectedIndex;
// x position of the palette, based on window width
static int palette_x_pos;


/*
 Draws the colour palette on the screen
 This is called from inside the "display" function
 @param window_width - Width of the window
 @param window_height - Height of the window
*/
static void Display(int window_width, int window_height) {
 palette_x_pos = window_width - 50;
 // draw the button for each colour (these are not from the Button class! they are implemented here)
 glBegin(GL_QUADS);
 int xPos = palette_x_pos;
 int yPos = 50;
 for (int i = 0; i < 5; i++) {
  // Draw border for the colour
  //  different coloured border depending on whether it is selected or not
  if (i == selectedIndex) {
   glColor3f(0.6f, 0.6f, 0.6f);
  }
  else {
   glColor3f(0.2f, 0.2f, 0.2f);
  }
  glVertex2f(xPos, window_height - yPos);
  glVertex2f(xPos + 50, window_height - yPos);
  glVertex2f(xPos + 50, window_height - (yPos + 50));
  glVertex2f(xPos, window_height - (yPos + 50));
  // Now draw the colour box itself
  glColor3f(colours[i].r, colours[i].g, colours[i].b);
  glVertex2f(xPos + 2, window_height - (yPos + 2));
  glVertex2f(xPos + 46, window_height - (yPos + 2));
  glVertex2f(xPos + 46, window_height - (yPos + 46));
  glVertex2f(xPos + 2, window_height - (yPos + 46));
  yPos += 49;
 }
 glEnd();
}


/*
 Checks if (x,y) coordinate is within a given rect
 @param x - x coordinate of point to test
 @param y - y coordinate of point to test
 @param x_pos - x coordinate of the rect (top left)
 @param y_pos - y coordinate of the rect (top left)
 @param width - width of the rect
 @param height - height of the rect
 @return True if the point lies within the rect
*/
static bool checkInside(int x, int y, int x_pos, int y_pos, int width, int height) {
 if (x >= x_pos) {
  if (y >= y_pos) {
   if (x < x_pos + width) {
    if (y < y_pos + height) {
     return true;
    }
   }
  }
 }
 return false;
}


/*
 Handles mouse pressed events for the colour palette
 @param button - Mouse button pressed
 @param state - State of mouse event (down or up)
 @param x - The x coordinate of the mouse when pressed
 @param y - The y coordinate of the mouse when pressed
 @return Has the colour palette handled the event?
*/
static bool Pressed(int button, int state, int x, int y) {
 if (button == GLUT_LEFT_BUTTON) {
  if (state == GLUT_UP) {
   int xPos = palette_x_pos;
   int yPos = 50;
   for (int i = 0; i < 5; i++) {
    // Check if the mouse is inside each colour rect
    if (checkInside(x, y, xPos, yPos, 50, 50)) {
     // select the colour
     selectedIndex = i;
     selectedColour = colours[i];
     return true;
    }
    yPos += 49;
   }
  }
 }
 // block the event from continuing if the mouse is over the colour palette
 return checkInside(x, y, palette_x_pos, 50, 50, 245);
}

};