3 // SuperTux - A Jump'n Run
4 // Copyright (C) 2004 Matthias Braun <matze@braunis.de
6 // This program is free software; you can redistribute it and/or
7 // modify it under the terms of the GNU General Public License
8 // as published by the Free Software Foundation; either version 2
9 // of the License, or (at your option) any later version.
11 // This program is distributed in the hope that it will be useful,
12 // but WITHOUT ANY WARRANTY; without even the implied warranty of
13 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 // GNU General Public License for more details.
16 // You should have received a copy of the GNU General Public License
17 // along with this program; if not, write to the Free Software
18 // Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
25 #include "utils/lispreader.h"
26 #include "utils/lispwriter.h"
30 #include "app/globals.h"
33 using namespace SuperTux;
35 Camera::Camera(Sector* newsector)
36 : sector(newsector), do_backscrolling(true), scrollchange(NONE),
37 auto_idx(0), auto_t(0)
47 Camera::get_translation() const
53 Camera::read(LispReader& reader)
57 reader.read_string("mode", modename);
58 if(modename == "normal") {
61 do_backscrolling = true;
62 reader.read_bool("backscrolling", do_backscrolling);
63 } else if(modename == "autoscroll") {
66 lisp_object_t* cur = 0;
67 reader.read_lisp("path", cur);
69 throw std::runtime_error("No path specified in autoscroll camera.");
72 while(!lisp_nil_p(cur)) {
73 if(strcmp(lisp_symbol(lisp_car(lisp_car(cur))), "point") != 0) {
74 std::cerr << "Warning: unknown token in camera path.\n";
78 LispReader reader(lisp_cdr(lisp_car(cur)));
81 if(!reader.read_float("x", point.position.x) ||
82 !reader.read_float("y", point.position.y)) {
83 throw std::runtime_error("x and y missing in point of camerapath");
85 reader.read_float("speed", speed);
87 scrollpoints.push_back(point);
91 } else if(modename == "manual") {
94 std::stringstream str;
95 str << "invalid camera mode '" << modename << "'found in worldfile.";
96 throw std::runtime_error(str.str());
101 Camera::write(LispWriter& writer)
103 writer.start_list("camera");
106 writer.write_string("mode", "normal");
107 writer.write_bool("backscrolling", do_backscrolling);
108 } else if(mode == AUTOSCROLL) {
109 writer.write_string("mode", "autoscroll");
110 writer.start_list("path");
111 for(std::vector<ScrollPoint>::iterator i = scrollpoints.begin();
112 i != scrollpoints.end(); ++i) {
113 writer.start_list("point");
114 writer.write_float("x", i->position.x);
115 writer.write_float("y", i->position.y);
116 writer.write_float("speed", i->speed);
117 writer.end_list("point");
120 writer.end_list("path");
121 } else if(mode == MANUAL) {
122 writer.write_string("mode", "manual");
125 writer.end_list("camera");
129 Camera::reset(const Vector& tuxpos)
131 translation.x = tuxpos.x - screen->w/3 * 2;
132 translation.y = tuxpos.y - screen->h/2;
136 static const float EPSILON = .00001;
137 static const float max_speed_y = 1.4;
140 Camera::action(float elapsed_time)
143 scroll_normal(elapsed_time);
144 else if(mode == AUTOSCROLL)
145 scroll_autoscroll(elapsed_time);
149 Camera::keep_in_bounds()
151 float width = sector->solids->get_width() * 32;
152 float height = sector->solids->get_height() * 32;
154 // don't scroll before the start or after the level's end
155 if(translation.y > height - screen->h)
156 translation.y = height - screen->h;
157 if(translation.y < 0)
159 if(translation.x > width - screen->w)
160 translation.x = width - screen->w;
161 if(translation.x < 0)
166 Camera::scroll_normal(float elapsed_time)
169 Player* player = sector->player;
171 // check that we don't have division by zero later
172 if(elapsed_time < EPSILON)
175 /****** Vertical Scrolling part ******/
176 bool do_y_scrolling = true;
178 if(player->dying || sector->solids->get_height() == 19)
179 do_y_scrolling = false;
182 // target_y is the high we target our scrolling at. This is not always the
183 // high of the player, but if he is jumping upwards we should use the
184 // position where he last touched the ground.
186 if(player->fall_mode == Player::JUMPING)
187 target_y = player->last_ground_y + player->base.height;
189 target_y = player->base.y + player->base.height;
191 // delta_y is the distance we'd have to travel to directly reach target_y
192 float delta_y = translation.y - (target_y - screen->h/2);
193 // speed is the speed the camera would need to reach target_y in this frame
194 float speed_y = delta_y / elapsed_time;
196 // limit the camera speed when jumping upwards
197 if(player->fall_mode != Player::FALLING
198 && player->fall_mode != Player::TRAMPOLINE_JUMP) {
199 if(speed_y > max_speed_y)
200 speed_y = max_speed_y;
201 else if(speed_y < -max_speed_y)
202 speed_y = -max_speed_y;
205 // finally scroll with calculated speed
206 translation.y -= speed_y * elapsed_time;
209 /****** Horizontal scrolling part *******/
211 // our camera is either in leftscrolling, rightscrolling or nonscrollingmode.
213 // when suddenly changing directions while scrolling into the other direction.
214 // abort scrolling, since tux might be going left/right at a relatively small
215 // part of the map (like when jumping upwards)
216 if((player->dir == ::LEFT && scrollchange == RIGHT)
217 || (player->dir == ::RIGHT && scrollchange == LEFT))
219 // when in left 1/3rd of screen scroll left
220 if(player->base.x < translation.x + screen->w/3 - 16 && do_backscrolling)
222 // scroll right when in right 1/3rd of screen
223 else if(player->base.x > translation.x + screen->w/3*2 + 16)
224 scrollchange = RIGHT;
226 // calculate our scroll target depending on scroll mode
228 if(scrollchange == LEFT)
229 target_x = player->base.x - screen->w/3*2;
230 else if(scrollchange == RIGHT)
231 target_x = player->base.x - screen->w/3;
233 target_x = translation.x;
235 // that's the distance we would have to travel to reach target_x
236 float delta_x = translation.x - target_x;
237 // the speed we'd need to travel to reach target_x in this frame
238 float speed_x = 1.3 * delta_x / elapsed_time;
241 float maxv = 1.3 * (1 + fabsf(player->physic.get_velocity_x() * 1.3));
244 else if(speed_x < -maxv)
248 translation.x -= speed_x * elapsed_time;
254 Camera::scroll_autoscroll(float elapsed_time)
256 Player* player = sector->player;
261 if(auto_t - elapsed_time >= 0) {
262 translation += current_dir * elapsed_time;
263 auto_t -= elapsed_time;
265 // do the rest of the old movement
266 translation += current_dir * auto_t;
267 elapsed_time -= auto_t;
270 // construct path for next point
271 if(auto_idx+1 >= scrollpoints.size()) {
275 Vector distance = scrollpoints[auto_idx+1].position
276 - scrollpoints[auto_idx].position;
277 current_dir = distance.unit() * scrollpoints[auto_idx].speed;
278 auto_t = distance.norm() / scrollpoints[auto_idx].speed;
280 // do movement for the remaining time
281 translation += current_dir * elapsed_time;
282 auto_t -= elapsed_time;