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.
24 #include "lispwriter.h"
31 Camera::Camera(Sector* newsector)
32 : sector(newsector), do_backscrolling(true), scrollchange(NONE),
33 auto_idx(0), auto_t(0)
43 Camera::get_translation() const
49 Camera::read(LispReader& reader)
53 reader.read_string("mode", modename);
54 if(modename == "normal") {
57 do_backscrolling = true;
58 reader.read_bool("backscrolling", do_backscrolling);
59 } else if(modename == "autoscroll") {
62 lisp_object_t* cur = 0;
63 reader.read_lisp("path", cur);
65 throw std::runtime_error("No path specified in autoscroll camera.");
68 while(!lisp_nil_p(cur)) {
69 if(strcmp(lisp_symbol(lisp_car(lisp_car(cur))), "point") != 0) {
70 std::cerr << "Warning: unknown token in camera path.\n";
74 LispReader reader(lisp_cdr(lisp_car(cur)));
77 if(!reader.read_float("x", point.position.x) ||
78 !reader.read_float("y", point.position.y)) {
79 throw std::runtime_error("x and y missing in point of camerapath");
81 reader.read_float("speed", speed);
83 scrollpoints.push_back(point);
87 } else if(modename == "manual") {
90 std::stringstream str;
91 str << "invalid camera mode '" << modename << "'found in worldfile.";
92 throw std::runtime_error(str.str());
97 Camera::write(LispWriter& writer)
99 writer.start_list("camera");
102 writer.write_string("mode", "normal");
103 writer.write_bool("backscrolling", do_backscrolling);
104 } else if(mode == AUTOSCROLL) {
105 writer.write_string("mode", "autoscroll");
106 writer.start_list("path");
107 for(std::vector<ScrollPoint>::iterator i = scrollpoints.begin();
108 i != scrollpoints.end(); ++i) {
109 writer.start_list("point");
110 writer.write_float("x", i->position.x);
111 writer.write_float("y", i->position.y);
112 writer.write_float("speed", i->speed);
113 writer.end_list("point");
116 writer.end_list("path");
117 } else if(mode == MANUAL) {
118 writer.write_string("mode", "manual");
121 writer.end_list("camera");
125 Camera::reset(const Vector& tuxpos)
127 translation.x = tuxpos.x - screen->w/3 * 2;
128 translation.y = tuxpos.y - screen->h/2;
132 static const float EPSILON = .00001;
133 static const float max_speed_y = 1.4;
136 Camera::action(float elapsed_time)
139 scroll_normal(elapsed_time);
140 else if(mode == AUTOSCROLL)
141 scroll_autoscroll(elapsed_time);
145 Camera::keep_in_bounds()
147 float width = sector->solids->get_width() * 32;
148 float height = sector->solids->get_height() * 32;
150 // don't scroll before the start or after the level's end
151 if(translation.y > height - screen->h)
152 translation.y = height - screen->h;
153 if(translation.y < 0)
155 if(translation.x > width - screen->w)
156 translation.x = width - screen->w;
157 if(translation.x < 0)
162 Camera::scroll_normal(float elapsed_time)
165 Player* player = sector->player;
167 // check that we don't have division by zero later
168 if(elapsed_time < EPSILON)
171 /****** Vertical Scrolling part ******/
172 bool do_y_scrolling = true;
174 if(player->dying || sector->solids->get_height() == 19)
175 do_y_scrolling = false;
178 // target_y is the high we target our scrolling at. This is not always the
179 // high of the player, but if he is jumping upwards we should use the
180 // position where he last touched the ground.
182 if(player->fall_mode == Player::JUMPING)
183 target_y = player->last_ground_y + player->base.height;
185 target_y = player->base.y + player->base.height;
187 // delta_y is the distance we'd have to travel to directly reach target_y
188 float delta_y = translation.y - (target_y - screen->h/2);
189 // speed is the speed the camera would need to reach target_y in this frame
190 float speed_y = delta_y / elapsed_time;
192 // limit the camera speed when jumping upwards
193 if(player->fall_mode != Player::FALLING
194 && player->fall_mode != Player::TRAMPOLINE_JUMP) {
195 if(speed_y > max_speed_y)
196 speed_y = max_speed_y;
197 else if(speed_y < -max_speed_y)
198 speed_y = -max_speed_y;
201 // finally scroll with calculated speed
202 translation.y -= speed_y * elapsed_time;
205 /****** Horizontal scrolling part *******/
207 // our camera is either in leftscrolling, rightscrolling or nonscrollingmode.
209 // when suddenly changing directions while scrolling into the other direction.
210 // abort scrolling, since tux might be going left/right at a relatively small
211 // part of the map (like when jumping upwards)
212 if((player->dir == ::LEFT && scrollchange == RIGHT)
213 || (player->dir == ::RIGHT && scrollchange == LEFT))
215 // when in left 1/3rd of screen scroll left
216 if(player->base.x < translation.x + screen->w/3 - 16 && do_backscrolling)
218 // scroll right when in right 1/3rd of screen
219 else if(player->base.x > translation.x + screen->w/3*2 + 16)
220 scrollchange = RIGHT;
222 // calculate our scroll target depending on scroll mode
224 if(scrollchange == LEFT)
225 target_x = player->base.x - screen->w/3*2;
226 else if(scrollchange == RIGHT)
227 target_x = player->base.x - screen->w/3;
229 target_x = translation.x;
231 // that's the distance we would have to travel to reach target_x
232 float delta_x = translation.x - target_x;
233 // the speed we'd need to travel to reach target_x in this frame
234 float speed_x = 1.3 * delta_x / elapsed_time;
237 float maxv = 1.3 * (1 + fabsf(player->physic.get_velocity_x() * 1.3));
240 else if(speed_x < -maxv)
244 translation.x -= speed_x * elapsed_time;
250 Camera::scroll_autoscroll(float elapsed_time)
252 Player* player = sector->player;
257 if(auto_t - elapsed_time >= 0) {
258 translation += current_dir * elapsed_time;
259 auto_t -= elapsed_time;
261 // do the rest of the old movement
262 translation += current_dir * auto_t;
263 elapsed_time -= auto_t;
266 // construct path for next point
267 if(auto_idx+1 >= scrollpoints.size()) {
271 Vector distance = scrollpoints[auto_idx+1].position
272 - scrollpoints[auto_idx].position;
273 current_dir = distance.unit() * scrollpoints[auto_idx].speed;
274 auto_t = distance.norm() / scrollpoints[auto_idx].speed;
276 // do movement for the remaining time
277 translation += current_dir * elapsed_time;
278 auto_t -= elapsed_time;