labyrinth: d46f0947a96d src/level.c

labyrinth

view src/level.c @ 1:d46f0947a96d

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author	John Tsiombikas <nuclear@member.fsf.org>
date	Fri, 06 Feb 2015 00:34:04 +0200
parents	8ba79034e8a6
children	c8826e5ebec1

line source

1 #include <stdio.h>

2 #include <stdlib.h>

3 #include <string.h>

4 #include <ctype.h>

5 #include <math.h>

6 #include "opengl.h"

7 #include "level.h"

9 #define C_WALL '#'

10 #define C_PILLAR 'o'

11 #define C_START 's'

12 #define C_GOLD 'x'

14 #define IS_SOLID(x) ((x) == C_WALL)

17 void level_init(struct level *lvl)

18 {

19 memset(lvl, 0, sizeof *lvl);

20 lvl->cell_size = 3.0;

21 lvl->cell_height = 2.5;

22 lvl->floor_tex_scale = lvl->wall_tex_scale = lvl->ceil_tex_scale = 1.0;

23 }

25 static void clean_line(char *buf)

26 {

27 char *end = buf + strlen(buf) - 1;

29 if(end <= buf) return;

31 while(end >= buf && !isprint(*end)) {

32 *end-- = 0;

33 }

34 }

36 int level_load(struct level *lvl, const char *fname)

37 {

38 FILE *fp;

39 char buf[256];

40 int i, size[2], nlines;

42 if(!(fp = fopen(fname, "r"))) {

43 fprintf(stderr, "failed to open file: %s\n", fname);

44 return -1;

45 }

47 if(!fgets(buf, sizeof buf, fp)) {

48 fprintf(stderr, "level file %s is empty\n", fname);

49 fclose(fp);

50 return -1;

51 }

52 if(sscanf(buf, "s %dx%d", size, size + 1) != 2) {

53 fprintf(stderr, "level file %s doesn't start with size definition\n", fname);

54 fclose(fp);

55 return -1;

56 }

57 if(size[0] > MAX_LEVEL_SIZE || size[1] > MAX_LEVEL_SIZE) {

58 fprintf(stderr, "level size %dx%d is larger than compile-time maximum (%d)\n", size[0], size[1], MAX_LEVEL_SIZE);

59 fclose(fp);

60 return -1;

61 }

63 lvl->num_cells[0] = size[0];

64 lvl->num_cells[1] = size[1];

66 nlines = 0;

67 while(fgets(buf, sizeof buf, fp)) {

68 if(nlines >= size[0]) {

69 fprintf(stderr, "warning: level contains more lines than specified, ignoring the rest\n");

70 break;

71 }

72 clean_line(buf);

74 for(i=0; buf[i]; i++) {

75 if(i >= size[1]) {

76 fprintf(stderr, "warning: line %d is longer than the level size definition says. Skipping the rest.\n", nlines + 1);

77 break;

78 }

79 lvl->cells[nlines][i] = buf[i];

81 if(buf[i] == C_START) {

82 lvl->start_pos[0] = i;

83 lvl->start_pos[1] = nlines;

84 printf("start cell found (%d,%d)\n", lvl->start_pos[0], lvl->start_pos[1]);

85 }

86 if(buf[i] == C_GOLD) {

87 level_cell_to_pos(lvl, i, nlines, lvl->goal_pos, lvl->goal_pos + 1);

88 printf("gold cell found (%d, %d)\n", i, nlines);

89 }

90 }

91 nlines++;

92 }

94 fclose(fp);

95 return 0;

96 }

99 static int clamp(int x, int low, int high)

100 {

101 return x < low ? low : (x > high ? high : x);

102 }

103

104 void level_pos_to_cell(struct level *lvl, float x, float y, int *res_cx, int *res_cy)

105 {

106 int cx = (int)(x / lvl->cell_size + 0.5);

107 int cy = (int)(y / lvl->cell_size + 0.5);

108

109 *res_cx = clamp(cx, 0, lvl->num_cells[1] - 1);

110 *res_cy = clamp(cy, 0, lvl->num_cells[0] - 1);

111 }

112

113 void level_cell_to_pos(struct level *lvl, int cx, int cy, float *resx, float *resy)

114 {

115 cx = clamp(cx, 0, lvl->num_cells[1] - 1);

116 cy = clamp(cy, 0, lvl->num_cells[0] - 1);

117

118 *resx = (float)cx * lvl->cell_size;

119 *resy = (float)cy * lvl->cell_size;

120 }

121

122 int level_cell(struct level *lvl, int cx, int cy)

123 {

124 cx = clamp(cx, 0, lvl->num_cells[1] - 1);

125 cy = clamp(cy, 0, lvl->num_cells[0] - 1);

126

127 return lvl->cells[cy][cx];

128 }

129

130 int level_cell_at(struct level *lvl, float x, float y)

131 {

132 int cx, cy;

133 level_pos_to_cell(lvl, x, y, &cx, &cy);

134 return level_cell(lvl, cx, cy);

135 }

136

137 int level_obj_pos(struct level *lvl, int objname, float *resx, float *resy)

138 {

139 int i, j;

140

141 for(i=0; i<lvl->num_cells[0]; i++) {

142 for(j=0; j<lvl->num_cells[1]; j++) {

143 if(lvl->cells[i][j] == objname) {

144 level_cell_to_pos(lvl, j, i, resx, resy);

145 return 1;

146 }

147 }

148 }

149 return 0;

150 }

151

152 /* NOTE: this function could be simpler */

153 int level_collide(struct level *lvl, float rad, float x, float y, float *dxp, float *dyp)

154 {

155 int i, val, cxy[2], collided = 0;

156 float pos[2], dir[2], center[2], len;

157 int adj_cxy[2];

158

159 pos[0] = x;

160 pos[1] = y;

161 dir[0] = *dxp;

162 dir[1] = *dyp;

163

164 /* clamp the direction magnitude (manhattan) to the cell size */

165 for(i=0; i<2; i++) {

166 if(dir[i] > lvl->cell_size) dir[i] = lvl->cell_size;

167 if(dir[i] < -lvl->cell_size) dir[i] = -lvl->cell_size;

168 }

169

170 level_pos_to_cell(lvl, pos[0], pos[1], cxy, cxy + 1);

171 level_cell_to_pos(lvl, cxy[0], cxy[1], center, center + 1);

172

173 /* check collision and clamp dx/dy with each of the 4 directions */

174 for(i=0; i<4; i++) {

175 float wall_pos, dist;

176 int axis = (i & 2) >> 1;

177 int sign = (i & 1) ? -1 : 1;

178

179 adj_cxy[0] = cxy[0];

180 adj_cxy[1] = cxy[1];

181 adj_cxy[axis] += sign;

182

183 val = level_cell(lvl, adj_cxy[0], adj_cxy[1]);

184

185 if(!IS_SOLID(val)) continue;

186

187 wall_pos = center[axis] + (lvl->cell_size * 0.5 - rad) * (float)sign;

188 dist = fabs(wall_pos - pos[axis]);

189

190 if(dir[axis] * (float)sign > dist) {

191 dir[axis] = (float)sign * dist;

192 collided = 1;

193 }

194 }

195

196 /* finally to make sure we don't slip through cracks in corners, also check

197 * the destination cell

198 */

199 len = sqrt(dir[0] * dir[0] + dir[1] * dir[1]);

200 pos[0] += dir[0] + dir[0] / len * rad;

201 pos[1] += dir[1] + dir[1] / len * rad;

202

203 val = level_cell_at(lvl, pos[0], pos[1]);

204 if(IS_SOLID(val)) {

205 dir[0] = dir[1] = 0;

206 }

207

208

209 *dxp = dir[0];

210 *dyp = dir[1];

211 return collided;

212 }

213

214 static void wall_faces(float x, float y, float width, float height, float uscale, float vscale)

215 {

216 float u0 = 0.5 - 0.5 * uscale;

217 float u1 = 0.5 + 0.5 * uscale;

218 float v0 = 0.5 - 0.5 * vscale;

219 float v1 = 0.5 + 0.5 * vscale;

220

221 width /= 2.0;

222

223 glNormal3f(0, 0, 1);

224 glTexCoord2f(u0, v1); glVertex3f(x - width, 0, y + width);

225 glTexCoord2f(u1, v1); glVertex3f(x + width, 0, y + width);

226 glTexCoord2f(u1, v0); glVertex3f(x + width, height, y + width);

227 glTexCoord2f(u0, v0); glVertex3f(x - width, height, y + width);

228 glNormal3f(0, 0, -1);

229 glTexCoord2f(u0, v0); glVertex3f(x - width, height, y - width);

230 glTexCoord2f(u1, v0); glVertex3f(x + width, height, y - width);

231 glTexCoord2f(u1, v1); glVertex3f(x + width, 0, y - width);

232 glTexCoord2f(u0, v1); glVertex3f(x - width, 0, y - width);

233 glNormal3f(1, 0, 0);

234 glTexCoord2f(u0, v1); glVertex3f(x + width, 0, y + width);

235 glTexCoord2f(u1, v1); glVertex3f(x + width, 0, y - width);

236 glTexCoord2f(u1, v0); glVertex3f(x + width, height, y - width);

237 glTexCoord2f(u0, v0); glVertex3f(x + width, height, y + width);

238 glNormal3f(-1, 0, 0);

239 glTexCoord2f(u0, v0); glVertex3f(x - width, height, y + width);

240 glTexCoord2f(u1, v0); glVertex3f(x - width, height, y - width);

241 glTexCoord2f(u1, v1); glVertex3f(x - width, 0, y - width);

242 glTexCoord2f(u0, v1); glVertex3f(x - width, 0, y + width);

243 }

244

245 void level_draw(struct level *lvl)

246 {

247 static int first = 1;

248 int i, j, k;

249

250 set_mtl_diffuse(1, 1, 1, 1);

251 set_mtl_specular(0, 0, 0);

252

253 glMatrixMode(GL_TEXTURE);

254 glLoadIdentity();

255 glScalef(lvl->wall_tex_scale, lvl->wall_tex_scale, lvl->wall_tex_scale);

256

257 glEnable(GL_TEXTURE_2D);

258

259 /* draw walls */

260 glBindTexture(GL_TEXTURE_2D, lvl->wall_tex);

261 glBegin(GL_QUADS);

262 for(i=0; i<lvl->num_cells[0]; i++) {

263 int cy = i;

264 for(j=0; j<lvl->num_cells[1]; j++) {

265 float x, y;

266 int cx = j;

267 int c = level_cell(lvl, cx, cy);

268

269 level_cell_to_pos(lvl, cx, cy, &x, &y);

270

271 if(c == C_WALL) {

272 wall_faces(x, y, lvl->cell_size, lvl->cell_height, 1, 1);

273 } else if(c == C_PILLAR) {

274 wall_faces(x, y, 0.2, lvl->cell_height, 0.04, 1);

275 }

276

277 if(first) putchar(c);

278 }

279 if(first) putchar('\n');

280 }

281 glEnd();

282

283 /* draw floor & ceiling */

284 for(k=0; k<2; k++) {

285 int do_floor = k == 0;

286 float height, normy;

287

288 if(do_floor) {

289 glBindTexture(GL_TEXTURE_2D, lvl->floor_tex);

290 glScalef(lvl->floor_tex_scale, lvl->floor_tex_scale, lvl->floor_tex_scale);

291 height = 0;

292 normy = 1;

293 glFrontFace(GL_CCW);

294 } else {

295 glBindTexture(GL_TEXTURE_2D, lvl->ceil_tex);

296 glScalef(lvl->ceil_tex_scale, lvl->ceil_tex_scale, lvl->ceil_tex_scale);

297 height = lvl->cell_height;

298 normy = -1;

299 glFrontFace(GL_CW);

300 }

301

302 glBegin(GL_TRIANGLES);

303 for(i=0; i<lvl->num_cells[0]; i++) {

304 int cy = i;

305 for(j=0; j<lvl->num_cells[1]; j++) {

306 float x, y;

307 int cx = j;

308 int c = level_cell(lvl, cx, cy);

309

310 level_cell_to_pos(lvl, cx, cy, &x, &y);

311

312 if(c != C_WALL) {

313 float hsz = lvl->cell_size / 2.0f;

314

315 glNormal3f(0, normy, 0);

316 glTexCoord2f(0.5, 0.5); glVertex3f(x, height, y);

317 glTexCoord2f(0.0, 0.0); glVertex3f(x - hsz, height, y + hsz);

318 glTexCoord2f(1.0, 0.0); glVertex3f(x + hsz, height, y + hsz);

319 glTexCoord2f(0.5, 0.5); glVertex3f(x, height, y);

320 glTexCoord2f(1.0, 0.0); glVertex3f(x + hsz, height, y + hsz);

321 glTexCoord2f(1.0, 1.0); glVertex3f(x + hsz, height, y - hsz);

322 glTexCoord2f(0.5, 0.5); glVertex3f(x, height, y);

323 glTexCoord2f(1.0, 1.0); glVertex3f(x + hsz, height, y - hsz);

324 glTexCoord2f(0.0, 1.0); glVertex3f(x - hsz, height, y - hsz);

325 glTexCoord2f(0.5, 0.5); glVertex3f(x, height, y);

326 glTexCoord2f(0.0, 1.0); glVertex3f(x - hsz, height, y - hsz);

327 glTexCoord2f(0.0, 0.0); glVertex3f(x - hsz, height, y + hsz);

328 }

329 }

330 }

331 glEnd();

332 }

333

334 glFrontFace(GL_CCW); /* restore front-face mode */

335 glDisable(GL_TEXTURE_2D);

336

337 glLoadIdentity(); /* restore the texture matrix to identity */

338 glMatrixMode(GL_MODELVIEW);

339

340 /* draw other objects

341 for(i=0; i<lvl->num_cells[0]; i++) {

342 int cy = i;

343 for(j=0; j<lvl->num_cells[1]; j++) {

344 float x, y;

345 int cx = j;

346 int c = level_cell(lvl, cx, cy);

347

348 level_cell_to_pos(lvl, cx, cy, &x, &y);

349

350 switch(c) {

351 case C_PILLAR:

352 break;

353 }

354 }

355 }

356 */

357

358 first = 0;

359 }