y3s2-gui-project/src/maze.cpp

#include "maze.h"

#include <cmath>

#include <GL/gl.h>
#include <GL/glu.h>
#include <GL/glut.h>

#include "utils.hpp"

constexpr double PI = 3.14159265358979;

MazeScreen::MazeScreen(const std::vector<std::vector<int>>& maze): 
	maze(maze), 
	angleX(0), 
	mouseCapture(false),
	posX(1),
	posZ(1) {}

void MazeScreen::display() {
	glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
	glMatrixMode(GL_MODELVIEW);
	glLoadIdentity();

	//configures the camera with the position_x and position_z variables
	gluLookAt(
		posX, 
		0, 
		posZ, 
		posX + cos((angleX * PI) / 180) * 3, 
		0, 
		posZ - sin((angleX * PI) / 180) * 3, 
		0, 
		1, 
		0
	);

	for (int i = 0; i < maze.size(); i++) {
		for (int j = 0; j < maze[i].size(); j++) {
			switch (maze[i][j]) {
			case -1:
				glPushMatrix();
				glColor3f(1, 0, 0);
				glTranslatef(i, 0, j);
				glutWireCube(1);
				glPopMatrix();
				break;
			case 1:
				glPushMatrix();
				// Scale green by X
				auto green = Utils::clamp<float>(Utils::nummap<float>(abs(i - posX), 0, 3, 0, 1), 0, 1);
				// Scale blue by Z
				auto blue = Utils::clamp<float>(Utils::nummap<float>(abs(j - posZ), 0, 3, 0, 1), 0, 1);
				glColor3f(1, green, blue);
				glTranslatef(i, 0, j);
				if (solid) {
					glutSolidCube(1);
				}
				else {
					glutWireCube(1);
				}
				glPopMatrix();
				break;
			}
		}
	}

	glFlush();
	glutSwapBuffers();
}

void MazeScreen::keyboard(unsigned char key, int x, int y) {
	if (key == '\e') {
		mouseCapture = false;
		glutSetCursor(GLUT_CURSOR_INHERIT);
	}
	else if (key == ' ') {
		solid = !solid;
	} 
	else if (key == 'w') {
		forceX += 1;
	}
	else if (key == 's') {
		forceX -= 1;
	}
	else if (key == 'a') {
		forceZ -= 1;
	}
	else if (key == 'd') {
		forceZ += 1;
	}
	glutPostRedisplay();
}

void MazeScreen::keyboardUp(unsigned char key, int x, int y) {
	if (key == 'w') {
		forceX -= 1;
	}
	else if (key == 's') {
		forceX += 1;
	}
	else if (key == 'a') {
		forceZ += 1;
	}
	else if (key == 'd') {
		forceZ -= 1;
	}
}

int gameTime;

void MazeScreen::idle() {
	int newTime = glutGet(GLUT_ELAPSED_TIME);
	auto deltaTime = (newTime - gameTime) / 1000.0;
	gameTime = newTime;

	posX += forceX * deltaTime * cos(angleX * PI / 180) + forceZ * deltaTime * sin(angleX * PI / 180);
	posZ += forceZ * deltaTime * cos(angleX * PI / 180) - forceX * deltaTime * sin(angleX * PI / 180);

	glutPostRedisplay();
}

void MazeScreen::passiveMotion(int x, int y) {
	if (mouseCapture) {
		auto centerX = glutGet(GLUT_WINDOW_WIDTH) / 2;
		auto centerY = glutGet(GLUT_WINDOW_HEIGHT) / 2;

		auto diffX = x - centerX;
		auto diffY = x - centerY;

		// only left-right movement
		angleX -= diffX;

		if (x != centerX || y != centerY) {
			glutWarpPointer(centerX, centerY);
		}
		glutPostRedisplay();
	}
}

void MazeScreen::mouse(int button, int state, int x, int y) {
	if (button == GLUT_LEFT_BUTTON) {
		auto centerX = glutGet(GLUT_WINDOW_WIDTH) / 2;
		auto centerY = glutGet(GLUT_WINDOW_HEIGHT) / 2;
		glutWarpPointer(centerX, centerY);
		mouseCapture = true;
		glutSetCursor(GLUT_CURSOR_NONE);
	} 
	else if (button == GLUT_RIGHT_BUTTON) {
		mouseCapture = false;
		glutSetCursor(GLUT_CURSOR_INHERIT);
	}
}