OpenGL/GLFW/GLM - keyboard input unresponsive - c++

Question

I have been following along with this tutorial series, whilst customising the code for my own goals (to render a 3D point cloud). I am able to render and move the point cloud around based on the mouse_input callback and can scroll in/out using the scroll callback. From what I've read/understood, the camera should be able to orbit around the point cloud (model) via the keyboard input. I am using W,S,A,D as forward, back, left, right inputs. I've tried lowercase and uppercase input (dont know if that makes a difference). I cant seem to get a response from the model.
I have gone over the code a few times and really can't see where I am going wrong.
Code below.
I am using Visual Studio 2017 Community.
Source.cpp
#include <glad/glad.h>
#include <C:\\Users\\jhansen\\Desktop\\OpenGL\\glad\\KHR\\khrplatform.h>
#include <C:\\Users\\jhansen\\Desktop\\OpenGL\\glad\\glad.c>
#include <GLFW/glfw3.h>
#include <glm/glm.hpp>
#include <glm/gtc/matrix_transform.hpp>
#include <glm/gtc/type_ptr.hpp>
#include <Shader.h>
#include <Camera.h>
#include <iostream>
void framebuffer_size_callback(GLFWwindow* window, int width, int height);
void mouse_callback(GLFWwindow* window, double xpos, double ypos);
void scroll_callback(GLFWwindow* window, double xoffset, double yoffset);
void processInput(GLFWwindow *window);
// settings
const unsigned int SCR_WIDTH = 800;
const unsigned int SCR_HEIGHT = 800;
// camera
Camera camera(glm::vec3(0.0f, 0.0f, 3.0f));
float lastX = SCR_WIDTH / 2.0f;
float lastY = SCR_HEIGHT / 2.0f;
bool firstMouse = true;
// timing
float deltaTime = 0.0f; // time between current frame and last frame
float lastFrame = 0.0f;
int main()
{
// glfw: initialize and configure
// ------------------------------
glfwInit();
glfwWindowHint(GLFW_CONTEXT_VERSION_MAJOR, 3);
glfwWindowHint(GLFW_CONTEXT_VERSION_MINOR, 3);
glfwWindowHint(GLFW_OPENGL_PROFILE, GLFW_OPENGL_CORE_PROFILE);
//glfwWindowHint(GLFW_OPENGL_FORWARD_COMPAT, GL_TRUE); // uncomment this statement to fix compilation on OS X
// glfw window creation
// --------------------
GLFWwindow* window = glfwCreateWindow(SCR_WIDTH, SCR_HEIGHT, "LearnOpenGL", NULL, NULL);
if (window == NULL)
{
std::cout << "Failed to create GLFW window" << std::endl;
glfwTerminate();
return -1;
}
glfwMakeContextCurrent(window);
glfwSetFramebufferSizeCallback(window, framebuffer_size_callback);
glfwSetCursorPosCallback(window, mouse_callback);
glfwSetScrollCallback(window, scroll_callback);
// tell GLFW to capture our mouse
glfwSetInputMode(window, GLFW_CURSOR, GLFW_CURSOR_NORMAL);
// glad: load all OpenGL function pointers
// ---------------------------------------
if (!gladLoadGLLoader((GLADloadproc)glfwGetProcAddress))
{
std::cout << "Failed to initialize GLAD" << std::endl;
return -1;
}
// configure global opengl state
// -----------------------------
glEnable(GL_DEPTH_TEST);
Shader ourShader("VertexShader.vs",
"FragShader.fs");
// set up vertex data (and buffer(s)) and configure vertex attributes
// ------------------------------------------------------------------
float vertices[] = {
-0.5f, -0.5f, 0.0f, // left
0.5f, -0.5f, 0.0f, // right
0.0f, 0.5f, 0.0f // top
};
struct Point
{
float x;
float y;
float z;
};
Point points[32000];
// Generate 32000 points
for (int i = 0; i < 32000; i++)
{
points[i].x = (float)((rand() % SCR_WIDTH) + 1);
points[i].y = (float)((rand() % SCR_WIDTH) + 1);
points[i].z = (float)((rand() % SCR_WIDTH) + 1);
// X Coords to Normalised Device coordinates
if (points[i].x > 400)
{
points[i].x = points[i].x * 0.00125f;
}
else if (points[i].x < 400)
{
points[i].x = points[i].x * -0.00125f;
}
else if (points[i].x == 400)
{
points[i].x = 0.0f;
}
// Y Coords to Normalised Device coordinates
if (points[i].y > 400)
{
points[i].y = points[i].y * 0.00125f;
}
else if (points[i].y < 400)
{
points[i].y = points[i].y * -0.00125f;
}
else if (points[i].y == 400)
{
points[i].y = 0.0f;
}
// Z Coords to Normalised Device coordinates
if (points[i].z > 400)
{
points[i].z = points[i].z * 0.00125f;
}
else if (points[i].z < 400)
{
points[i].z = points[i].z * -0.00125f;
}
else if (points[i].z == 400)
{
points[i].z = 0.0f;
}
//cout << points[i].x << ", " << points[i].y << ", " << points[i].z << endl;
}
unsigned int VBO, VAO;
glGenVertexArrays(1, &VAO);
glGenBuffers(1, &VBO);
// bind the Vertex Array Object first, then bind and set vertex buffer(s), and then configure vertex attributes(s).
glBindVertexArray(VAO);
glBindBuffer(GL_ARRAY_BUFFER, VBO);
glBufferData(GL_ARRAY_BUFFER, sizeof(points), points, GL_STATIC_DRAW);
glVertexAttribPointer(0, 3, GL_FLOAT, GL_FALSE, 3 * sizeof(float), (void*)0);
glEnableVertexAttribArray(0);
// note that this is allowed, the call to glVertexAttribPointer registered VBO as the vertex attribute's bound vertex buffer object so afterwards we can safely unbind
glBindBuffer(GL_ARRAY_BUFFER, 0);
// You can unbind the VAO afterwards so other VAO calls won't accidentally modify this VAO, but this rarely happens. Modifying other
// VAOs requires a call to glBindVertexArray anyways so we generally don't unbind VAOs (nor VBOs) when it's not directly necessary.
glBindVertexArray(0);
// uncomment this call to draw in wireframe polygons.
//glPolygonMode(GL_FRONT_AND_BACK, GL_LINE);
// render loop
// -----------
while (!glfwWindowShouldClose(window))
{
// input
// -----
processInput(window);
// render
// ------
glClearColor(0.2f, 0.3f, 0.3f, 1.0f);
glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
// activate shader
ourShader.use();
// pass projection matrix to shader (note that in this case it could change every frame)
glm::mat4 projection = glm::perspective(glm::radians(camera.Zoom), (float)SCR_WIDTH / (float)SCR_HEIGHT, 0.1f, 100.0f);
ourShader.setMat4("projection", projection);
// camera/view transformation
glm::mat4 view = camera.GetViewMatrix();
ourShader.setMat4("view", view);
glm::mat4 model;
model = glm::rotate(model, glm::radians(-55.0f), glm::vec3(1.0f, 0.3f, 0.5f));
ourShader.setMat4("model", model);
// draw our points array
//glUseProgram(shaderProgram);
glBindVertexArray(VAO); // seeing as we only have a single VAO there's no need to bind it every time, but we'll do so to keep things a bit more organized
glPointSize(3.0f);
glDrawArrays(GL_POINTS, 0, 32000);
// glBindVertexArray(0); // no need to unbind it every time
// glfw: swap buffers and poll IO events (keys pressed/released, mouse moved etc.)
// -------------------------------------------------------------------------------
glfwSwapBuffers(window);
glfwPollEvents();
}
// optional: de-allocate all resources once they've outlived their purpose:
// ------------------------------------------------------------------------
glDeleteVertexArrays(1, &VAO);
glDeleteBuffers(1, &VBO);
// glfw: terminate, clearing all previously allocated GLFW resources.
// ------------------------------------------------------------------
glfwTerminate();
return 0;
}
// process all input: query GLFW whether relevant keys are pressed/released this frame and react accordingly
// ---------------------------------------------------------------------------------------------------------
void processInput(GLFWwindow *window)
{
if (glfwGetKey(window, GLFW_KEY_ESCAPE) == GLFW_PRESS)
glfwSetWindowShouldClose(window, true);
if (glfwGetKey(window, GLFW_KEY_W) == GLFW_PRESS)
camera.ProcessKeyboard(FORWARD, deltaTime);
if (glfwGetKey(window, GLFW_KEY_S) == GLFW_PRESS)
camera.ProcessKeyboard(BACKWARD, deltaTime);
if (glfwGetKey(window, GLFW_KEY_A) == GLFW_PRESS)
camera.ProcessKeyboard(LEFT, deltaTime);
if (glfwGetKey(window, GLFW_KEY_D) == GLFW_PRESS)
camera.ProcessKeyboard(RIGHT, deltaTime);
}
// glfw: whenever the window size changed (by OS or user resize) this callback function executes
// ---------------------------------------------------------------------------------------------
void framebuffer_size_callback(GLFWwindow* window, int width, int height)
{
// make sure the viewport matches the new window dimensions; note that width and
// height will be significantly larger than specified on retina displays.
glViewport(0, 0, width, height);
}
// glfw: whenever the mouse moves, this callback is called
// -------------------------------------------------------
void mouse_callback(GLFWwindow* window, double xpos, double ypos)
{
if (firstMouse)
{
lastX = xpos;
lastY = ypos;
firstMouse = false;
}
float xoffset = xpos - lastX;
float yoffset = lastY - ypos; // reversed since y-coordinates go from bottom to top
lastX = xpos;
lastY = ypos;
camera.ProcessMouseMovement(xoffset, yoffset);
}
// glfw: whenever the mouse scroll wheel scrolls, this callback is called
// ----------------------------------------------------------------------
void scroll_callback(GLFWwindow* window, double xoffset, double yoffset)
{
camera.ProcessMouseScroll(yoffset);
}
Camera.h
#ifndef CAMERA_H
#define CAMERA_H
#include <glad/glad.h>
#include <glm/glm.hpp>
#include <glm/gtc/matrix_transform.hpp>
#include <vector>
// Defines several possible options for camera movement. Used as abstraction to stay away from window-system specific input methods
enum Camera_Movement {
FORWARD,
BACKWARD,
LEFT,
RIGHT
};
// Default camera values
const float YAW = -90.0f;
const float PITCH = 0.0f;
const float SPEED = 2.5f;
const float SENSITIVTY = 0.1f;
const float ZOOM = 45.0f;
// An abstract camera class that processes input and calculates the corresponding Eular Angles, Vectors and Matrices for use in OpenGL
class Camera
{
public:
// Camera Attributes
glm::vec3 Position;
glm::vec3 Front;
glm::vec3 Up;
glm::vec3 Right;
glm::vec3 WorldUp;
// Eular Angles
float Yaw;
float Pitch;
// Camera options
float MovementSpeed;
float MouseSensitivity;
float Zoom;
// Constructor with vectors
Camera(glm::vec3 position = glm::vec3(0.0f, 0.0f, 0.0f), glm::vec3 up = glm::vec3(0.0f, 1.0f, 0.0f), float yaw = YAW, float pitch = PITCH) : Front(glm::vec3(0.0f, 0.0f, -1.0f)), MovementSpeed(SPEED), MouseSensitivity(SENSITIVTY), Zoom(ZOOM)
{
Position = position;
WorldUp = up;
Yaw = yaw;
Pitch = pitch;
updateCameraVectors();
}
// Constructor with scalar values
Camera(float posX, float posY, float posZ, float upX, float upY, float upZ, float yaw, float pitch) : Front(glm::vec3(0.0f, 0.0f, -1.0f)), MovementSpeed(SPEED), MouseSensitivity(SENSITIVTY), Zoom(ZOOM)
{
Position = glm::vec3(posX, posY, posZ);
WorldUp = glm::vec3(upX, upY, upZ);
Yaw = yaw;
Pitch = pitch;
updateCameraVectors();
}
// Returns the view matrix calculated using Eular Angles and the LookAt Matrix
glm::mat4 GetViewMatrix()
{
return glm::lookAt(Position, Position + Front, Up);
}
// Processes input received from any keyboard-like input system. Accepts input parameter in the form of camera defined ENUM (to abstract it from windowing systems)
void ProcessKeyboard(Camera_Movement direction, float deltaTime)
{
float velocity = MovementSpeed * deltaTime;
if (direction == FORWARD)
Position += Front * velocity;
if (direction == BACKWARD)
Position -= Front * velocity;
if (direction == LEFT)
Position -= Right * velocity;
if (direction == RIGHT)
Position += Right * velocity;
}
// Processes input received from a mouse input system. Expects the offset value in both the x and y direction.
void ProcessMouseMovement(float xoffset, float yoffset, GLboolean constrainPitch = true)
{
xoffset *= MouseSensitivity;
yoffset *= MouseSensitivity;
Yaw += xoffset;
Pitch += yoffset;
// Make sure that when pitch is out of bounds, screen doesn't get flipped
if (constrainPitch)
{
if (Pitch > 89.0f)
Pitch = 89.0f;
if (Pitch < -89.0f)
Pitch = -89.0f;
}
// Update Front, Right and Up Vectors using the updated Eular angles
updateCameraVectors();
}
// Processes input received from a mouse scroll-wheel event. Only requires input on the vertical wheel-axis
void ProcessMouseScroll(float yoffset)
{
if (Zoom >= 1.0f && Zoom <= 45.0f)
Zoom -= yoffset;
if (Zoom <= 1.0f)
Zoom = 1.0f;
if (Zoom >= 45.0f)
Zoom = 45.0f;
}
private:
// Calculates the front vector from the Camera's (updated) Eular Angles
void updateCameraVectors()
{
// Calculate the new Front vector
glm::vec3 front;
front.x = cos(glm::radians(Yaw)) * cos(glm::radians(Pitch));
front.y = sin(glm::radians(Pitch));
front.z = sin(glm::radians(Yaw)) * cos(glm::radians(Pitch));
Front = glm::normalize(front);
// Also re-calculate the Right and Up vector
Right = glm::normalize(glm::cross(Front, WorldUp)); // Normalize the vectors, because their length gets closer to 0 the more you look up or down which results in slower movement.
Up = glm::normalize(glm::cross(Right, Front));
}
};
#endif

Answer 1

This might help you as a good reference for this is out of my Player::move() method where different movements are enumerated types.
// -----------------------------------------------------------------------
// move()
// Move The Player In A Desired Direction
void Player::move( Action action, float fDeltaTime ) {
Vector3 v3LookDirection;
v3LookDirection = m_v3LookCenter - m_v3Position;
switch ( action ) {
case MOVING_FORWARD: {
// Prevent Vertical Motion
v3LookDirection.m_fY = 0.0f;
m_v3Position += v3LookDirection * fDeltaTime * m_fLinearSpeed;
m_v3LookCenter += v3LookDirection * fDeltaTime * m_fLinearSpeed;
break;
}
case MOVING_BACK: {
// Prevent Vertical Motion
v3LookDirection.m_fY = 0.0f;
m_v3Position -= v3LookDirection * fDeltaTime * m_fLinearSpeed;
m_v3LookCenter -= v3LookDirection * fDeltaTime * m_fLinearSpeed;
break;
}
case MOVING_LEFT: {
// Get "Side" Direction & Prevent Vertical Motion
v3LookDirection.m_fY = v3LookDirection.m_fX;
v3LookDirection.m_fX = -v3LookDirection.m_fZ;
v3LookDirection.m_fZ = v3LookDirection.m_fY;
v3LookDirection.m_fY = 0.0f;
m_v3Position -= v3LookDirection * fDeltaTime * m_fLinearSpeed;
m_v3LookCenter -= v3LookDirection * fDeltaTime * m_fLinearSpeed;
break;
}
case MOVING_RIGHT: {
// Get "Side" Direction & Prevent Vertical Motion
v3LookDirection.m_fY = v3LookDirection.m_fX;
v3LookDirection.m_fX = -v3LookDirection.m_fZ;
v3LookDirection.m_fZ = v3LookDirection.m_fY;
v3LookDirection.m_fY = 0.0f;
m_v3Position += v3LookDirection * fDeltaTime * m_fLinearSpeed;
m_v3LookCenter += v3LookDirection * fDeltaTime * m_fLinearSpeed;
break;
}
case LOOKING_LEFT: {
/*float fSin = -sin( fDeltaTime * m_fAngularSpeed );
float fCos = cos( fDeltaTime * m_fAngularSpeed );
m_v3LookCenter.m_fX = m_v3Position.m_fX + (-fSin * v3LookDirection.m_fZ + fCos * v3LookDirection.m_fX );
m_v3LookCenter.m_fZ = m_v3Position.m_fZ + ( fCos * v3LookDirection.m_fZ + fSin * v3LookDirection.m_fX );
break;*/
// Third Person
float fSin = sin( fDeltaTime * m_fAngularSpeed );
float fCos = -cos( fDeltaTime * m_fAngularSpeed );
m_v3Position.m_fX = m_v3LookCenter.m_fX + (-fSin * v3LookDirection.m_fZ + fCos * v3LookDirection.m_fX );
m_v3Position.m_fZ = m_v3LookCenter.m_fZ + ( fCos * v3LookDirection.m_fZ + fSin * v3LookDirection.m_fX );
break;
}
case LOOKING_RIGHT: {
/*float fSin = sin( fDeltaTime * m_fAngularSpeed );
float fCos = cos( fDeltaTime * m_fAngularSpeed );
m_v3LookCenter.m_fX = m_v3Position.m_fX + (-fSin * v3LookDirection.m_fZ + fCos * v3LookDirection.m_fX );
m_v3LookCenter.m_fZ = m_v3Position.m_fZ + ( fCos * v3LookDirection.m_fZ + fSin * v3LookDirection.m_fX );
break;*/
// Third Person
float fSin = -sin( fDeltaTime * _fAngularSpeed );
float fCos = -cos( fDeltaTime * _fAngularSpeed );
m_v3Position.m_fX = m_v3LookCenter.m_fX + (-fSin * v3LookDirection.m_fZ + fCos * v3LookDirection.m_fX );
m_v3Position.m_fZ = m_v3LookCenter.m_fZ + ( fCos * v3LookDirection.m_fZ + fSin * v3LookDirection.m_fX );
break;
}
case LOOKING_UP: {
m_v3LookCenter.m_fY -= fDeltaTime * m_fAngularSpeed * m_MouseLookState;
// Check Maximum Values
if ( m_v3LookCenter.m_fY > (m_v3Position.m_fY + m_fMaxUp ) ) {
m_v3LookCenter.m_fY = m_v3Position.m_fY + m_fMaxUp;
} else if ( m_v3LookCenter.m_fY < (m_v3Position.m_fY - m_fMaxDown) ) {
m_v3LookCenter.m_fY = m_v3Position.m_fY - _fMaxDown;
}
break;
}
}
} // move
This is coming from an old project when I was learning OpenGL 1.0 (Legacy). Everything was done manually without existing libraries; even had to write a few vector libraries. This player class is independent from the Camera class but gets it's position and look direction vectors from it. These are tightly integrated into an GameOGL class that creates a window, message proc, message handler and sets up all of OpenGL stuff as well as a very large Scene class object. The math used here works as this belongs to a 3D Game Engine in which a Third Person View dungeon type game is made. Just make sure you are using the appropriate rotation matrices and trig methods for doing rotations based on the handedness of your 3D graph system.
Also the rotational motion that you are trying to achieve might be different. This causes the player - camera to turn left and right as if you are looking into the distance. The type of rotation you might want would be almost considered the inverse of that where your looking direction & distance remains fixed to the model but your camera is rotating through the world at a specific rotational velocity.