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 "lispwriter.h"
32 Camera::Camera(Sector* newsector)
33 : sector(newsector), do_backscrolling(true), scrollchange(NONE),
34 auto_idx(0), auto_t(0)
44 Camera::get_translation() const
50 Camera::read(LispReader& reader)
54 reader.read_string("mode", modename);
55 if(modename == "normal") {
58 do_backscrolling = true;
59 reader.read_bool("backscrolling", do_backscrolling);
60 } else if(modename == "autoscroll") {
63 lisp_object_t* cur = 0;
64 reader.read_lisp("path", cur);
66 throw std::runtime_error("No path specified in autoscroll camera.");
69 while(!lisp_nil_p(cur)) {
70 if(strcmp(lisp_symbol(lisp_car(lisp_car(cur))), "point") != 0) {
71 std::cerr << "Warning: unknown token in camera path.\n";
75 LispReader reader(lisp_cdr(lisp_car(cur)));
78 if(!reader.read_float("x", point.position.x) ||
79 !reader.read_float("y", point.position.y)) {
80 throw std::runtime_error("x and y missing in point of camerapath");
82 reader.read_float("speed", speed);
84 scrollpoints.push_back(point);
88 } else if(modename == "manual") {
91 std::stringstream str;
92 str << "invalid camera mode '" << modename << "'found in worldfile.";
93 throw std::runtime_error(str.str());
98 Camera::write(LispWriter& writer)
100 writer.start_list("camera");
103 writer.write_string("mode", "normal");
104 writer.write_bool("backscrolling", do_backscrolling);
105 } else if(mode == AUTOSCROLL) {
106 writer.write_string("mode", "autoscroll");
107 writer.start_list("path");
108 for(std::vector<ScrollPoint>::iterator i = scrollpoints.begin();
109 i != scrollpoints.end(); ++i) {
110 writer.start_list("point");
111 writer.write_float("x", i->position.x);
112 writer.write_float("y", i->position.y);
113 writer.write_float("speed", i->speed);
114 writer.end_list("point");
117 writer.end_list("path");
118 } else if(mode == MANUAL) {
119 writer.write_string("mode", "manual");
122 writer.end_list("camera");
126 Camera::reset(const Vector& tuxpos)
128 translation.x = tuxpos.x - screen->w/3 * 2;
129 translation.y = tuxpos.y - screen->h/2;
133 static const float EPSILON = .00001;
134 static const float max_speed_y = 1.4;
137 Camera::action(float elapsed_time)
140 scroll_normal(elapsed_time);
141 else if(mode == AUTOSCROLL)
142 scroll_autoscroll(elapsed_time);
146 Camera::keep_in_bounds()
148 float width = sector->solids->get_width() * 32;
149 float height = sector->solids->get_height() * 32;
151 // don't scroll before the start or after the level's end
152 if(translation.y > height - screen->h)
153 translation.y = height - screen->h;
154 if(translation.y < 0)
156 if(translation.x > width - screen->w)
157 translation.x = width - screen->w;
158 if(translation.x < 0)
163 Camera::scroll_normal(float elapsed_time)
166 Player* player = sector->player;
168 // check that we don't have division by zero later
169 if(elapsed_time < EPSILON)
172 /****** Vertical Scrolling part ******/
173 bool do_y_scrolling = true;
175 if(player->dying || sector->solids->get_height() == 19)
176 do_y_scrolling = false;
179 // target_y is the high we target our scrolling at. This is not always the
180 // high of the player, but if he is jumping upwards we should use the
181 // position where he last touched the ground.
183 if(player->fall_mode == Player::JUMPING)
184 target_y = player->last_ground_y + player->base.height;
186 target_y = player->base.y + player->base.height;
188 // delta_y is the distance we'd have to travel to directly reach target_y
189 float delta_y = translation.y - (target_y - screen->h/2);
190 // speed is the speed the camera would need to reach target_y in this frame
191 float speed_y = delta_y / elapsed_time;
193 // limit the camera speed when jumping upwards
194 if(player->fall_mode != Player::FALLING
195 && player->fall_mode != Player::TRAMPOLINE_JUMP) {
196 if(speed_y > max_speed_y)
197 speed_y = max_speed_y;
198 else if(speed_y < -max_speed_y)
199 speed_y = -max_speed_y;
202 // finally scroll with calculated speed
203 translation.y -= speed_y * elapsed_time;
206 /****** Horizontal scrolling part *******/
208 // our camera is either in leftscrolling, rightscrolling or nonscrollingmode.
210 // when suddenly changing directions while scrolling into the other direction.
211 // abort scrolling, since tux might be going left/right at a relatively small
212 // part of the map (like when jumping upwards)
213 if((player->dir == ::LEFT && scrollchange == RIGHT)
214 || (player->dir == ::RIGHT && scrollchange == LEFT))
216 // when in left 1/3rd of screen scroll left
217 if(player->base.x < translation.x + screen->w/3 - 16 && do_backscrolling)
219 // scroll right when in right 1/3rd of screen
220 else if(player->base.x > translation.x + screen->w/3*2 + 16)
221 scrollchange = RIGHT;
223 // calculate our scroll target depending on scroll mode
225 if(scrollchange == LEFT)
226 target_x = player->base.x - screen->w/3*2;
227 else if(scrollchange == RIGHT)
228 target_x = player->base.x - screen->w/3;
230 target_x = translation.x;
232 // that's the distance we would have to travel to reach target_x
233 float delta_x = translation.x - target_x;
234 // the speed we'd need to travel to reach target_x in this frame
235 float speed_x = 1.3 * delta_x / elapsed_time;
238 float maxv = 1.3 * (1 + fabsf(player->physic.get_velocity_x() * 1.3));
241 else if(speed_x < -maxv)
245 translation.x -= speed_x * elapsed_time;
251 Camera::scroll_autoscroll(float elapsed_time)
253 Player* player = sector->player;
258 if(auto_t - elapsed_time >= 0) {
259 translation += current_dir * elapsed_time;
260 auto_t -= elapsed_time;
262 // do the rest of the old movement
263 translation += current_dir * auto_t;
264 elapsed_time -= auto_t;
267 // construct path for next point
268 if(auto_idx+1 >= scrollpoints.size()) {
272 Vector distance = scrollpoints[auto_idx+1].position
273 - scrollpoints[auto_idx].position;
274 current_dir = distance.unit() * scrollpoints[auto_idx].speed;
275 auto_t = distance.norm() / scrollpoints[auto_idx].speed;
277 // do movement for the remaining time
278 translation += current_dir * elapsed_time;
279 auto_t -= elapsed_time;