ConsoleApplication1.cpp

#include <iostream>
#include <stdio.h>
#include <math.h>
#include <windows.h>
#include "VecFunctions.h"

void SetWindow(int Width, int Height)
{
	_COORD coord;
	coord.X = Width;
	coord.Y = Height;
	_SMALL_RECT Rect;
	Rect.Top = 0;
	Rect.Left = 0;
	Rect.Bottom = Height - 1;
	Rect.Right = Width - 1;
	HANDLE Handle = GetStdHandle(STD_OUTPUT_HANDLE);
	SetConsoleScreenBufferSize(Handle, coord);
	SetConsoleWindowInfo(Handle, TRUE, &Rect);
}

int main() {
	int width = 120 ;
	int height = 30 ;
	SetWindow(width, height);
	float aspect = (float)width / height;
	float pixelAspect = 11.0f / 24.0f;
	char gradient[] = " .:;/=123456789@";
	int gradientSize = std::size(gradient) - 2;

	wchar_t* screen = new wchar_t[width * height];
	HANDLE hConsole = CreateConsoleScreenBuffer(GENERIC_READ | GENERIC_WRITE, 0, NULL, CONSOLE_TEXTMODE_BUFFER, NULL);
	SetConsoleActiveScreenBuffer(hConsole);
	DWORD dwBytesWritten = 0;

	for (int t = 0; t < 10000; t++) {
		vec3 light = norm(vec3(-0.5, 0.5, -5.0));
		vec3 boxPos = vec3(0, 1, 0);
		for (int i = 0; i < width; i++) {
			for (int j = 0; j < height; j++) {
				vec2 uv = vec2(i, j) / vec2(width, height) * 2.0f - 1.0f;uv.x *= aspect * pixelAspect;
				vec3 ro = vec3(-6, 0, 0);vec3 rd = norm(vec3(2, uv));
				ro = rotateY(ro, 0.25);	rd = rotateY(rd, 0.25);	ro = rotateZ(ro, t * 0.01);	rd = rotateZ(rd, t * 0.01);
				float diff = 1;
				for (int k = 0; k < 5; k++) {
					float minIt = 99999;
					vec3 boxN = 0;
					vec2 intersection = box(ro-boxPos, rd, 1, boxN);
					vec3 n = 0;
					float albedo = 1;
					if (intersection.x > 0 && intersection.x < minIt) {
						minIt = intersection.x;
						n = boxN;
					}					
					if (minIt < 99999) {
						diff *= (dot(n, light) * 0.5 + 0.5) * albedo;
						ro = ro + rd * (minIt - 0.01);
						
					}
					else break;
				}
				int color = (int)(diff * 20);
				color = clamp(color, 0, gradientSize);
				char pixel = gradient[color];
				screen[i + j * width] = pixel;
			}
		}
		screen[width * height - 1] = '\0';
		WriteConsoleOutputCharacter(hConsole, screen, width * height, { 0, 0 }, &dwBytesWritten);
	}
}