dda line drawing

#include <iostream>

#include<cmath>

// GLEW

#define GLEW_STATIC

#include <GL/glew.h>

// GLFW

#include <GLFW/glfw3.h>

// Window dimensions

const GLuint WIDTH = 800, HEIGHT = 600;

void processInput(GLFWwindow* window);

using namespace std;

void lineDDA(int x0, int y0, int xEnd, int yEnd);

void setPixel(float x, float y);

int main()

{

glfwInit();

glfwWindowHint(GLFW_CONTEXT_VERSION_MAJOR, 3);

glfwWindowHint(GLFW_CONTEXT_VERSION_MINOR, 1);

glfwWindowHint(GLFW_OPENGL_PROFILE, GLFW_OPENGL_ANY_PROFILE);

glfwWindowHint(GLFW_RESIZABLE, GL_FALSE);

//glfwWindowHint(GLFW_MAXIMIZED, true);

//glfwWindowHint(GLFW_TRANSPARENT_FRAMEBUFFER, GLFW_TRUE);

GLFWwindow* window = glfwCreateWindow(WIDTH, HEIGHT, "zi xi", nullptr, nullptr);

//GLFWwindow* window = glfwCreateWindow(WIDTH, HEIGHT, "My Title", glfwGetPrimaryMonitor(), NULL);

glfwSetWindowOpacity(window, 0.8f);

glfwMakeContextCurrent(window);

while (!glfwWindowShouldClose(window))

{

// Clear the colorbuffer

glClearColor(1.0f, 0.7f, 1.0f, 1.0f);

glClear(GL_COLOR_BUFFER_BIT);

processInput(window);

lineDDA(0, 600, 800, 0);

// Swap the screen buffers

glfwSwapBuffers(window);

// Check if any events have been activiated (key pressed, mouse moved etc.) and call corresponding response functions

glfwPollEvents();

}

// Terminate GLFW, clearing any resources allocated by GLFW.

glfwTerminate();

return EXIT_SUCCESS;

}

void processInput(GLFWwindow* window)

{

if (glfwGetKey(window, GLFW_KEY_ESCAPE) == GLFW_PRESS)

glfwSetWindowShouldClose(window, true);

if (glfwGetKey(window, GLFW_KEY_1) == GLFW_PRESS)

cout << "1" << endl;

}

void lineDDA(int x0, int y0, int xEnd, int yEnd)

{

glPointSize(3);

glColor3f(1, 1, 0.3);

int dx = xEnd - x0, dy = yEnd - y0, steps, k;

float xIncrement, yIncrement, x = x0, y = y0;

if (dx > dy)

{

steps = dx;

}

else

{

steps = dy;

}

xIncrement = (float)dx / steps;

yIncrement = (float)dy / steps;

setPixel(x, y);

for (int k = 0; k < steps; k++)

{

x += xIncrement;

y += yIncrement;

setPixel(x, y);

}

}

void setPixel(float x, float y)

{

float newx = 2 * x / WIDTH - 1;

float newy = 2 * y / HEIGHT - 1;

glBegin(GL_POINTS);

glVertex2f(newx, newy);

     glEnd();

}