1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
|
/*
* Copyright (C) 2021 P. J. McDermott
*
* This file is part of Dodge Balls
*
* Dodge Balls is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* Dodge Balls is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with Dodge Balls. If not, see <http://www.gnu.org/licenses/>.
*/
#include <math.h>
#include <stdlib.h>
#include "ball.h"
#include "collision.h"
#include "map.h"
#include "tileset.h"
#include "output.h"
struct db_ball {
int cx;
int cy;
double x;
double y;
int r;
double a;
int d;
int sr;
double s;
struct db_tileset *tilesets;
int gid;
struct db_map *map;
struct db_ball *next;
};
struct db_ball *
db_ball_new(int x, int y, int r, int a, int d, int sr, double s,
struct db_tileset *tilesets, int gid, struct db_map *map,
struct db_ball *prev)
{
struct db_ball *ball;
ball = calloc(1, sizeof(*ball));
if (ball == NULL) {
db_err("Failed to allocate memory");
return NULL;
}
db_dbg("Ball at (%d,%d)", x, y);
if (sr == 0) {
ball->x = x;
ball->y = y;
} else {
ball->cx = x;
ball->cy = y;
ball->x = x + cos(a * (M_PI / 180)) * sr;
ball->y = y + sin(a * (M_PI / 180)) * sr;
}
ball->r = r;
ball->a = a;
ball->d = d;
ball->sr = sr;
ball->s = s;
ball->tilesets = tilesets;
ball->gid = gid;
ball->map = map;
if (prev != NULL) {
prev->next = ball;
}
return ball;
}
void
db_balls_move(struct db_ball *ball)
{
if (ball->sr == 0) {
ball->x += cos(ball->a * (M_PI / 180));
ball->y += sin(ball->a * (M_PI / 180));
} else {
ball->a = fmod(ball->a + ball->d * ball->s, 360);
ball->x = ball->cx + cos(ball->a * (M_PI / 180)) * ball->sr;
ball->y = ball->cy + sin(ball->a * (M_PI / 180)) * ball->sr;
db_dbg("Spinning ball angle %f (speed %f, direction %d)",
ball->a, ball->s, ball->d);
}
if (ball->next != NULL) {
db_balls_move(ball->next);
}
}
static void
_db_ball_bounce(struct db_ball *ball, double col_x, double col_y)
{
double col_a;
col_a = atan2(col_y - ball->y, col_x - ball->x) * 180 / M_PI;
ball->a = fmod(2 * col_a - ball->a - 180, 360);
}
void
db_balls_collisions(struct db_ball *ball)
{
SDL_Rect wall;
int map_tw;
int map_th;
int x_min;
int x_max;
int y_min;
int y_max;
int x;
int y;
double col_x;
double col_y;
struct db_ball *other;
wall.w = map_tw = db_map_get_tilewidth (ball->map);
wall.h = map_th = db_map_get_tileheight(ball->map);
x_min = floor((ball->x - ball->r) / map_tw);
x_max = ceil ((ball->x + ball->r) / map_tw);
y_min = floor((ball->y - ball->r) / map_th);
y_max = ceil ((ball->y + ball->r) / map_th);
for (y = y_min; y < y_max; ++y) {
for (x = x_min; x < x_max; ++x) {
if (db_map_tile_ball_collides(ball->map, x, y)) {
wall.x = x * map_tw;
wall.y = y * map_th;
if (db_col_cir_rect(ball->x, ball->y, ball->r,
&wall, &col_x, &col_y)){
_db_ball_bounce(ball, col_x, col_y);
}
}
}
}
/* Spinning balls shouldn't collide with any other balls */
if (ball->sr == 0) {
for (other = ball->next; other != NULL; other = other->next) {
if (other->sr == 0 && db_col_pt_cir_cir(
ball->x, ball->y, ball->r,
other->x, other->y, other->r,
&col_x, &col_y)) {
_db_ball_bounce(ball , col_x, col_y);
_db_ball_bounce(other, col_x, col_y);
}
}
}
if (ball->next != NULL) {
db_balls_collisions(ball->next);
}
}
int
db_balls_player_collisions(struct db_ball *ball,
int player_x, int player_y, int player_r)
{
if (db_col_cir_cir(ball->x, ball->y, ball->r,
player_x, player_y, player_r)) {
return 1;
}
if (ball->next != NULL) {
return db_balls_player_collisions(ball->next,
player_x, player_y, player_r);
} else {
return 0;
}
}
void
db_balls_render(struct db_ball *ball, SDL_Renderer *renderer)
{
SDL_Rect dstrect;
dstrect.x = ball->x - ball->r;
dstrect.y = ball->y - ball->r;
dstrect.w = ball->r * 2;
dstrect.h = ball->r * 2;
db_dbg("Rendering ball (%dx%d) at (%d,%d)",
dstrect.w, dstrect.h, dstrect.x, dstrect.y);
db_tile_render(ball->tilesets, renderer, ball->gid, &dstrect);
if (ball->next != NULL) {
db_balls_render(ball->next, renderer);
}
}
|
