input.cpp

/*
 * The MIT License (MIT)
 *
 * Copyright (c) 2014 Christoph Brill
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 * THE SOFTWARE.
 */

#include <algorithm>
#include <cmath>

#include "input.h"
#include "global.h"
#include "tile.h"

struct s_input_state {
    bool left_mouse_down = false;
    bool right_mouse_down = false;
    bool middle_mouse_down = false;
} input_state;

struct s_viewport_state viewport_state;

double start_angle_rotate = 0.0;
double start_angle2 = 0.0;

double angle(int p1x, int p1y, int p2x, int p2y) {
    float xDiff = p2x - p1x;
    float yDiff = p2y - p1y;
    return -atan2(yDiff, xDiff) * (180 / M_PI);
}

void handle_mouse_motion(SDL_MouseMotionEvent &motion) {
    if (input_state.left_mouse_down) {
        viewport_state.angle_rotate = angle(motion.x, motion.y, (window_state.width / 2), (window_state.height / 2)) - start_angle_rotate;
    }
    if (input_state.right_mouse_down) {
        viewport_state.angle_tilt = std::max((window_state.height / 2) - motion.y, 0) * MAX_TILT / (window_state.height / 2);
    }
    if (input_state.middle_mouse_down) {
        long double _cos = std::cos(viewport_state.angle_rotate * M_PI / 180);
        long double _sin = std::sin(viewport_state.angle_rotate * M_PI / 180);
        player_state.latitude += (latsize(player_state.latitude, player_state.zoom)/TILE_SIZE) * (motion.yrel * _cos + motion.xrel * _sin) / std::cos(viewport_state.angle_tilt * M_PI / 180);
        // Cap between a latitude of -66° ad 80° due to the limitations of mercator
        player_state.latitude = std::min(player_state.latitude, 80.0);
        player_state.latitude = std::max(player_state.latitude, -66.0);
        player_state.longitude -= (lonsize(player_state.zoom)/TILE_SIZE) * (motion.xrel * _cos - motion.yrel * _sin);
    }
}

void handle_mouse_button_down(SDL_MouseButtonEvent &button) {
    if (button.button == 1) {
        input_state.left_mouse_down = true;
        start_angle_rotate = angle(button.x, button.y, (window_state.width / 2), (window_state.height / 2)) - viewport_state.angle_rotate;
    } else if (button.button == 3) {
        input_state.right_mouse_down = true;
        start_angle2 = angle(button.x, button.y, (window_state.width / 2), (window_state.height / 2)) - viewport_state.angle_tilt;
    } else if (button.button == 2) {
        input_state.middle_mouse_down = true;
    }
}

void handle_mouse_button_up(SDL_MouseButtonEvent &button) {
    if (button.button == 1) {
        input_state.left_mouse_down = false;
    } else if (button.button == 3) {
        input_state.right_mouse_down = false;
    } else if (button.button == 2) {
        input_state.middle_mouse_down = false;
    }
}

void handle_mouse_wheel(SDL_MouseWheelEvent &wheel) {
    player_state.zoom += wheel.y;
    player_state.zoom = std::max(player_state.zoom, 1);
    player_state.zoom = std::min(player_state.zoom, 18);
}