week3

#include <GLFW/glfw3.h>
#include <cstring>
#include <stdlib.h>		  // srand, rand
#include <thread>         // std::this_thread::sleep_for
#include <chrono>         // std::chrono::seconds
#include "math.h"
#include <algorithm>


const int width = 640;
const int height = 480;

float* pixels = new float[width*height * 3];

void drawPixel(const int& i, const int& j, const float& red, const float& green, const float& blue)
{
	pixels[(i + width* j) * 3 + 0] = red;
	pixels[(i + width* j) * 3 + 1] = green;
	pixels[(i + width* j) * 3 + 2] = blue;
}

void drawLine(const int& i0, const int& j0, const int& i1, const int& j1, const float& red, const float& green, const float& blue)
{
	for (int i = i0; i <= i1; i++)
	{
		const int j = (j1 - j0)*(i - i0) / (i1 - i0) + j0;

		drawPixel(i, j, red, green, blue);
	}
}


bool circle(const int x, const int y)
{
	const int x_c = 300;
	const int y_c = 300;
	const int r = 20;

	int f = (x - x_c)*(x - x_c) + (y - y_c)*(y - y_c) - r*r;

	if (f > 0) return false;
	else return true;
}

int main(void)
{
	GLFWwindow* window;

	/* Initialize the library */
	if (!glfwInit())
		return -1;

	/* Create a windowed mode window and its OpenGL context */
	window = glfwCreateWindow(width, height, "Hello", NULL, NULL);
	if (!window)
	{
		glfwTerminate();
		return -1;
	}

	/* Make the window's context current */
	glfwMakeContextCurrent(window);

	/* Loop until the user closes the window */
	while (!glfwWindowShouldClose(window))
	{
		/* Render here */
		glClear(GL_COLOR_BUFFER_BIT);
		std::fill_n(pixels, width*height * 3, 1.0f);

		//#1
		drawLine(16, 76, 100, 10, 1.0f, 0.0f, 0.0f);
		drawLine(16, 77, 100, 11, 1.0f, 0.0f, 0.0f);
		drawLine(16, 78, 100, 12, 1.0f, 0.0f, 0.0f);

		//#2
		for (int i = 240; i < 320; i++)
		{
			for (int j = 63; j < 171; j++)
			{
				if (i == 319)
				{
					drawPixel(i, j, 0.0f, 0.0f, 0.0f);
				}
				else if (i == 240)
				{
					drawPixel(i, j, 0.0f, 0.0f, 0.0f);
				}
				if (j == 63)
				{
					drawPixel(i, j, 0.0f, 0.0f, 0.0f);
				}
				if (j == 170)
				{
					drawPixel(i, j, 0.0f, 0.0f, 0.0f);
				}

			}
		}
		//#3
		for (int i = 397; i < 592; i++)
		{
			for (int j = 63; j < 171; j++)
			{
				drawPixel(i, j, 0.0f, 1.0f, 0.0f);
			}
		}


		//#4
	

	 //  //#6
		//for (int i = 0; i < 640; i++)
		//{
		//	for (int j = 0; i < 480; j++)
		//	{
		//		if(circle(i,j)==true)
		//			drawPixel(i, j, 0.0f, 1.0f, 1.0f);
		//	}

		//}




		glDrawPixels(width, height, GL_RGB, GL_FLOAT, pixels);

		/* Swap front and back buffers */
		glfwSwapBuffers(window);

		/* Poll for and process events */
		glfwPollEvents();
	}

	glfwTerminate();
	return 0;
}