обнаружен многократно используемый символ, как исправить

Вот мои файлы: tPointt.h

#include <windows.h>
#include <glut.h>
#include <Math.h>
#include <vector>
#include <array>
#include <vector>
#include <ctime>

GLfloat ballXMax, ballXMin, ballYMax, ballYMin;
float ballRadius = 0.007f;
float PI = 3.14159265f;


class tPoint {
public:
    float x;
    float y;
    float R;

    int r;
    int g;
    int b;

    float speedX;
    float speedY;
    int move;

    tPoint();
    void Draw();
    void move_point();
};

tPointt.cpp

void tPoint::Draw() {

    glBegin(GL_TRIANGLE_FAN);
    glMatrixMode(GL_MODELVIEW);
    glLoadIdentity();
    glColor3ub(r, g, b);
    glVertex2f(x, y);
    for (int angle = 0; angle <= 360; angle += 10) {
        float _x = R * cos(angle * PI / 180);
        float _y = R * sin(angle * PI / 180);
        glColor3ub(r, g, b);
        glVertex2f(x + _x, y + _y);
    }
    glEnd();
}

void tPoint::move_point() {

    if (move == 1) {
        x += speedX;
        y += speedY;

        if (x > ballXMax) {
            x = ballXMax;
            speedX = -speedX;
        }
        else if (x < ballXMin) {
            x = ballXMin;
            speedX = -speedX;
        }
        if (y > ballYMax) {
            y = ballYMax;
            speedY = -speedY;
        }
        else if (y < ballYMin) {
            y = ballYMin;
            speedY = -speedY;
        }
    }
    else {
        x += rand() % 100 / 1000.f * pow(-1, rand() % 2);
        y += rand() % 100 / 1000.f * pow(-1, rand() % 2);

        if (x > ballXMax) {
            x = ballXMax;
            speedX = -speedX;
        }
        else if (x < ballXMin) {
            x = ballXMin;
            speedX = -speedX;
        }
        if (y > ballYMax) {
            y = ballYMax;
            speedY = -speedY;
        }
        else if (y < ballYMin) {
            y = ballYMin;
            speedY = -speedY;
        }
    }
}

main.cpp

extern GLfloat ballXMax, ballXMin, ballYMax, ballYMin;
extern float PI;
void reshape(GLsizei width, GLsizei height) {
    // Compute aspect ratio of the new window
    if (height == 0) height = 1;                // To prevent divide by 0
    GLfloat aspect = (GLfloat)width / (GLfloat)height;

    // Set the viewport to cover the new window
    glViewport(0, 0, width, height);

    // Set the aspect ratio of the clipping area to match the viewport
    glMatrixMode(GL_PROJECTION);  // To operate on the Projection matrix
    glLoadIdentity();             // Reset the projection matrix
    if (width >= height) {
        clipAreaXLeft = -1.0 * aspect;
        clipAreaXRight = 1.0 * aspect;
        clipAreaYBottom = -1.0;
        clipAreaYTop = 1.0;
    }
    else {
        clipAreaXLeft = -1.0;
        clipAreaXRight = 1.0;
        clipAreaYBottom = -1.0 / aspect;
        clipAreaYTop = 1.0 / aspect;
    }
    gluOrtho2D(clipAreaXLeft, clipAreaXRight, clipAreaYBottom, clipAreaYTop);
    ballXMin = clipAreaXLeft + ballRadius;
    ballXMax = clipAreaXRight - ballRadius;
    ballYMin = clipAreaYBottom + ballRadius;
    ballYMax = clipAreaYTop - ballRadius;
}

Вставил функции, в которых используются повторяющиеся переменные, как исправить можно? Писал extern в каждом файле, не особо помогло