rayfract: 87b6a11c920b src/utktext.cc

rayfract

view src/utktext.cc @ 2:87b6a11c920b

added gui stuff

author	John Tsiombikas <nuclear@siggraph.org>
date	Tue, 26 Oct 2010 08:49:09 +0300
parents
children	bf1d56975cc9

line source

1 #include <math.h>

2 #include <ctype.h>

3 #define GL_GLEXT_PROTOTYPES

4 #if defined(__APPLE__) && defined(__MACH__)

5 #include <GLUT/glut.h>

6 #else

7 #include <GL/glut.h>

8 #endif

9 #include <ft2build.h>

10 #include FT_FREETYPE_H

11 #include <vmath.h>

12 #include "utktext.h"

13 #include "utk_common.h"

15 #ifndef GL_BGRA

16 #define GL_BGRA 0x80E1

17 #endif

19 #ifndef GL_ABGR

20 #define GL_ABGR 0x8000

21 #endif

23 #ifdef UTK_BIG_ENDIAN

24 #define PIXFMT GL_ABGR

25 #else

26 #define PIXFMT GL_BGRA

27 #endif

29 #define MAX_CHARS 128

30 #define MAX_IMG_WIDTH 1024

31 #define SIZE_PIXELS(x) ((x) / 64)

33 struct Font {

34 unsigned int tex_id;

35 float scale; // this compensates if a higher res font is loaded in its stead, with a new CreateFont

36 float line_adv; // vertical advance to go to the next line

37 struct {

38 Vector2 pos, size; // glyph position (from origin) and size in normalized coords [0, 1]

39 float advance; // advance in normalized coords

40 Vector2 tc_pos, tc_sz; // tex coord box pos/size

41 } glyphs[MAX_CHARS];

42 };

44 static void BlitFontGlyph(Font *fnt, int x, int y, FT_GlyphSlot glyph, unsigned int *img, int xsz, int ysz);

45 static void CleanUp();

47 static FT_Library ft;

48 static Vector2 text_pos;

49 static float text_size = 1.0;

50 static Color text_color;

51 static Font *act_fnt;

53 #if !defined(GLIBC) && !defined(__GLIBC__)

54 float log2(float x) {

55 float res = 0.0;

56 while(x > 1.0) {

57 x /= 2.0;

58 res += 1.0;

59 }

60 return res;

61 }

62 #endif // _MSC_VER

65 static inline int NextPow2(int x)

66 {

67 float lg2 = log2((float)x);

68 return (int)pow(2.0f, (int)ceil(lg2));

69 }

72 unsigned int CreateFont(const char *fname, int font_size)

73 {

74 if(!ft) {

75 if(FT_Init_FreeType(&ft) != 0) {

76 fprintf(stderr, "failed to initialize freetype\n");

77 return 0;

78 }

79 atexit(CleanUp);

80 }

82 FT_Face face;

83 if(FT_New_Face(ft, fname, 0, &face) != 0) {

84 fprintf(stderr, "failed to load font: %s\n", fname);

85 return 0;

86 }

88 FT_Set_Pixel_Sizes(face, 0, font_size);

90 Font *fnt = new Font;

91 int max_width = MAX_CHARS * SIZE_PIXELS(face->bbox.xMax - face->bbox.xMin);

92 int foo_xsz = MAX_IMG_WIDTH;

93 int foo_ysz = SIZE_PIXELS(face->bbox.yMax - face->bbox.yMin) * max_width / foo_xsz;

95 int tex_xsz = NextPow2(foo_xsz);

96 int tex_ysz = NextPow2(foo_ysz);

98 unsigned int *img;

99 img = new unsigned int[tex_xsz * tex_ysz];

100 memset(img, 0, tex_xsz * tex_ysz * sizeof *img);

101

102 extern int xsz, ysz;

103 int vport_xsz = xsz, vport_ysz = ysz;

104

105 int max_glyph_y = 0;

106 int max_glyph_x = 0;

107 for(int i=0; i<MAX_CHARS; i++) {

108 FT_Load_Char(face, i, 0);

109 int width = SIZE_PIXELS(face->glyph->metrics.width);

110 int height = SIZE_PIXELS(face->glyph->metrics.height);

111

112 if(height > max_glyph_y) {

113 max_glyph_y = height;

114 }

115

116 if(width > max_glyph_x) {

117 max_glyph_x = width;

118 }

119 }

120

121 int gx = 0, gy = 0;

122 for(int i=0; i<MAX_CHARS; i++) {

123 FT_Load_Char(face, i, FT_LOAD_RENDER);

124 FT_GlyphSlot g = face->glyph;

125

126 int gwidth = SIZE_PIXELS(g->metrics.width);

127 int gheight = SIZE_PIXELS(g->metrics.height);

128

129 if(gx > MAX_IMG_WIDTH - gwidth) {

130 gx = 0;

131 gy += max_glyph_y;

132 }

133

134 BlitFontGlyph(fnt, gx, gy, g, img, tex_xsz, tex_ysz);

135 fnt->scale = 1.0;

136 fnt->line_adv = (float)SIZE_PIXELS(g->metrics.vertAdvance) / (float)vport_ysz;

137 fnt->glyphs[i].tc_pos.x = (float)gx / (float)tex_xsz;

138 fnt->glyphs[i].tc_pos.y = (float)gy / (float)tex_ysz;

139 fnt->glyphs[i].tc_sz.x = (float)gwidth / (float)tex_xsz;

140 fnt->glyphs[i].tc_sz.y = (float)gheight / (float)tex_ysz;

141 fnt->glyphs[i].size.x = (float)gwidth / (float)vport_xsz;

142 fnt->glyphs[i].size.y = (float)gheight / (float)vport_ysz;

143 fnt->glyphs[i].pos.x = (float)SIZE_PIXELS(g->metrics.horiBearingX) / (float)vport_xsz;

144 fnt->glyphs[i].pos.y = -(float)SIZE_PIXELS(g->metrics.horiBearingY) / (float)vport_ysz;

145 fnt->glyphs[i].advance = (float)SIZE_PIXELS(g->metrics.horiAdvance) / (float)vport_xsz;

146

147 gx += gwidth;

148 }

149

150 FT_Done_Face(face);

151

152 glGenTextures(1, &fnt->tex_id);

153 glBindTexture(GL_TEXTURE_2D, fnt->tex_id);

154 glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_REPEAT);

155 glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_REPEAT);

156 glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);

157 glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);

158 glTexImage2D(GL_TEXTURE_2D, 0, 4, tex_xsz, tex_ysz, 0, PIXFMT, GL_UNSIGNED_BYTE, img);

159

160 #ifdef DUMP_FONT_IMG

161 FILE *fp;

162 unsigned int *ptr = img;

163

164 if((fp = fopen("fnt.ppm", "wb"))) {

165 fprintf(fp, "P6\n%d %d\n255\n", tex_xsz, tex_ysz);

166

167 for(int i=0; i<tex_xsz * tex_ysz; i++) {

168 fputc((*ptr >> 24) & 0xff, fp);

169 fputc((*ptr >> 24) & 0xff, fp);

170 fputc((*ptr >> 24) & 0xff, fp);

171 ptr++;

172 }

173 fclose(fp);

174 }

175 #endif

176

177 delete [] img;

178

179 act_fnt = fnt;

180

181 return 1;

182 }

183

184 void DeleteFont(unsigned int fid)

185 {

186 }

187

188 unsigned int GetFont(const char *fname, int sz)

189 {

190 return 1;

191 }

192

193 bool BindFont(unsigned int fid)

194 {

195 return true;

196 }

197

198 void SetTextPos(const Vector2 &pos)

199 {

200 text_pos = pos;

201 }

202

203 Vector2 GetTextPos()

204 {

205 return text_pos;

206 }

207

208 void TextLineAdvance(int adv)

209 {

210 text_pos.y += (float)adv * act_fnt->line_adv;

211 }

212

213 void TextCRet()

214 {

215 text_pos.x = 0.0;

216 }

217

218 void SetTextSize(float sz)

219 {

220 text_size = sz;

221 }

222

223 float GetTextSize()

224 {

225 return text_size;

226 }

227

228 void SetTextColor(const Color &col)

229 {

230 text_color = col;

231 }

232

233 Color GetTextColor()

234 {

235 return text_color;

236 }

237

238 static void ImOverlay(const Vector2 &v1, const Vector2 &v2, const Color &col, unsigned int tex)

239 {

240 float l = v1.x * 2.0f - 1.0f;

241 float r = v2.x * 2.0f - 1.0f;

242 float u = -v1.y * 2.0f + 1.0f;

243 float d = -v2.y * 2.0f + 1.0f;

244

245 glMatrixMode(GL_PROJECTION);

246 glPushMatrix();

247 glLoadIdentity();

248 glMatrixMode(GL_MODELVIEW);

249 glPushMatrix();

250 glLoadIdentity();

251

252 glBindTexture(GL_TEXTURE_2D, tex);

253

254 glDisable(GL_DEPTH_TEST);

255 glDisable(GL_LIGHTING);

256 glDisable(GL_CULL_FACE);

257

258 glBegin(GL_QUADS);

259 glColor4f(col.r, col.g, col.b, col.a);

260 glTexCoord2f(0, 0);

261 glVertex2f(l, u);

262 glTexCoord2f(1, 0);

263 glVertex2f(r, u);

264 glTexCoord2f(1, 1);

265 glVertex2f(r, d);

266 glTexCoord2f(0, 1);

267 glVertex2f(l, d);

268 glEnd();

269

270 glEnable(GL_LIGHTING);

271 glEnable(GL_DEPTH_TEST);

272

273 glMatrixMode(GL_PROJECTION);

274 glPopMatrix();

275 glMatrixMode(GL_MODELVIEW);

276 glPopMatrix();

277 }

278

279 float PrintChar(char c)

280 {

281 // get texture coordinates for the glyph, and construct the texture matrix

282 float tx = act_fnt->glyphs[(int)c].tc_pos.x;

283 float ty = act_fnt->glyphs[(int)c].tc_pos.y;

284 float sx = act_fnt->glyphs[(int)c].tc_sz.x;

285 float sy = act_fnt->glyphs[(int)c].tc_sz.y;

286

287 float mat[] = {

288 sx, 0, tx, 0,

289 0, sy, ty, 0,

290 0, 0, 1, 0,

291 0, 0, 0, 1

292 };

293

294 glMatrixMode(GL_TEXTURE);

295 glPushMatrix();

296 glLoadMatrixf(mat);

297

298 Vector2 pos = text_pos + act_fnt->glyphs[(int)c].pos * act_fnt->scale;

299 ImOverlay(pos, pos + act_fnt->glyphs[(int)c].size * act_fnt->scale, text_color, act_fnt->tex_id);

300

301 glMatrixMode(GL_TEXTURE);

302 glPopMatrix();

303

304 return act_fnt->glyphs[(int)c].advance * act_fnt->scale;

305 }

306

307 // this function contains the preamble of all block text drawing functions (i.e. not printchar above)

308 static void PreDraw()

309 {

310 glMatrixMode(GL_PROJECTION);

311 glPushMatrix();

312 /*glLoadTransposeMatrixf(OrthoProj(2, 2, 0, 10).m);*/

313 glLoadIdentity();

314 glMatrixMode(GL_MODELVIEW);

315 glPushMatrix();

316 glLoadIdentity();

317 glMatrixMode(GL_TEXTURE);

318 glPushMatrix();

319 glLoadIdentity();

320

321 glEnable(GL_TEXTURE_2D);

322 glBindTexture(GL_TEXTURE_2D, act_fnt->tex_id);

323

324 glBegin(GL_QUADS);

325 glColor4f(text_color.r, text_color.g, text_color.b, text_color.a);

326 }

327

328 static void PostDraw()

329 {

330 glEnd();

331

332 glDisable(GL_TEXTURE_2D);

333

334 glMatrixMode(GL_TEXTURE);

335 glPopMatrix();

336 glMatrixMode(GL_MODELVIEW);

337 glPopMatrix();

338 glMatrixMode(GL_PROJECTION);

339 glPopMatrix();

340 }

341

342 float PrintString(const char *str, bool standalone)

343 {

344 if(standalone) PreDraw();

345

346 float start_x = text_pos.x;

347 while(*str) {

348 float tx = act_fnt->glyphs[(int)*str].tc_pos.x;

349 float ty = act_fnt->glyphs[(int)*str].tc_pos.y;

350 float sx = act_fnt->glyphs[(int)*str].tc_sz.x;

351 float sy = act_fnt->glyphs[(int)*str].tc_sz.y;

352

353 Vector2 tc1 = Vector2(tx, ty);

354 Vector2 tc2 = Vector2(tx + sx, ty + sy);

355

356 Vector2 v1 = text_pos + act_fnt->glyphs[(int)*str].pos * act_fnt->scale * text_size;

357 Vector2 v2 = v1 + act_fnt->glyphs[(int)*str].size * act_fnt->scale * text_size;

358 float l = v1.x * 2.0f - 1.0f;

359 float r = v2.x * 2.0f - 1.0f;

360 float u = -v1.y * 2.0f + 1.0f;

361 float d = -v2.y * 2.0f + 1.0f;

362

363 glTexCoord2f(tc1.x, tc1.y);

364 glVertex2f(l, u);

365 glTexCoord2f(tc2.x, tc1.y);

366 glVertex2f(r, u);

367 glTexCoord2f(tc2.x, tc2.y);

368 glVertex2f(r, d);

369 glTexCoord2f(tc1.x, tc2.y);

370 glVertex2f(l, d);

371

372 text_pos.x += act_fnt->glyphs[(int)*str++].advance * act_fnt->scale * text_size;

373 }

374

375 if(standalone) PostDraw();

376 return text_pos.x - start_x;

377 }

378

379 void PrintStringLines(const char **str, int lines)

380 {

381 PreDraw();

382

383 while(lines-- > 0) {

384 PrintString(*str++, false);

385 TextLineAdvance();

386 TextCRet();

387 }

388

389 PostDraw();

390 }

391

392 static void BlitFontGlyph(Font *fnt, int x, int y, FT_GlyphSlot glyph, unsigned int *img, int xsz, int ysz)

393 {

394 if(glyph->bitmap.pixel_mode != FT_PIXEL_MODE_GRAY) {

395 fprintf(stderr, "BlitFontGlyph: unsupported pixel mode: %d\n", glyph->bitmap.pixel_mode);

396 return;

397 }

398

399 unsigned int *dest = img + y * xsz + x;

400 unsigned char *src = glyph->bitmap.buffer;

401

402 for(int j=0; j<glyph->bitmap.rows; j++) {

403 for(int i=0; i<glyph->bitmap.width; i++) {

404 dest[i] = 0x00ffffff | ((unsigned int)src[i] << 24);

405 }

406 dest += xsz;

407 src += glyph->bitmap.pitch;

408 }

409 }

410

411 static void CleanUp()

412 {

413 FT_Done_FreeType(ft);

414 }

415

416 float GetMaxDescent()

417 {

418 Font *fnt = act_fnt;

419

420 float max_descent = 0.0f;

421

422 for(int i=0; i<MAX_CHARS; i++) {

423 float des = fnt->glyphs[i].pos.y + fnt->glyphs[i].size.y;

424 if(isprint(i) && des > max_descent) {

425 max_descent = des;

426 }

427 }

428

429 return max_descent;

430 }

431

432 float GetLineAdvance()

433 {

434 return act_fnt->line_adv;

435 }

436

437 float GetTextWidth(const char *str)

438 {

439 float width = 0;

440 while(*str) {

441 width += act_fnt->glyphs[(int)*str++].advance * act_fnt->scale * text_size;

442 }

443 return width;

444 }