openglcanvas.cpp 24.3 KB
Newer Older
Luis Peñaranda's avatar
Luis Peñaranda committed
1 2
#include <QtGui>
#ifdef NEEDGLEE
3
  #include "GLee.h"
Luis Peñaranda's avatar
Luis Peñaranda committed
4 5 6
#endif
#include "openglcanvas.h"
#include <cmath>
7 8
#include <sys/types.h>  // for fstat, getpwuid, getuid
#include <sys/stat.h>   // for fstat
Luis Penaranda's avatar
Luis Penaranda committed
9 10 11 12
#ifdef _WIN32
  #include <stdlib.h>   // for getenv (TODO: use getenv_s)
#else
  #include <pwd.h>      // for getpwuid
13
#endif
14 15
#include <cstdio>       // for fopen, fclose, getc
#include <cstring>
Luis Penaranda's avatar
Luis Penaranda committed
16
#ifdef _MSC_VER
17 18
  #include <direct.h>
  #define GET_WORKDIR _getcwd
19 20
  #define OPEN_FILE _open
  #define LSEEK_FD _lseek
Luis Penaranda's avatar
Luis Penaranda committed
21 22 23 24 25
  #define FOPEN_RO(_descriptor,_filename) \
    if(fopen_s(&(_descriptor),_filename,"r")){ \
        fprintf(stderr,"unable to open file '%s'\n",_filename); \
        exit(-1); \
    }
26
#else
27
  // unistd was included above
28
  #define GET_WORKDIR getcwd
29 30
  #define OPEN_FILE open
  #define LSEEK_FD lseek
Luis Penaranda's avatar
Luis Penaranda committed
31
  #define FOPEN_RO(_descriptor,_filename) \
Luis Penaranda's avatar
Luis Penaranda committed
32 33
    _descriptor=fopen(_filename,"r"); \
    if((_descriptor)==NULL){ \
Luis Penaranda's avatar
Luis Penaranda committed
34 35 36
        fprintf(stderr,"unable to open file '%s'\n",_filename); \
        exit(-1); \
    }
37
#endif
Luis Peñaranda's avatar
Luis Peñaranda committed
38 39

#define PROGNAME "pano_interface"
40 41
#define VERT_SHADER_FILE "test_vertex_shader.vert"
#define FRAG_SHADER_FILE "fragment_shader.frag"
Luis Peñaranda's avatar
Luis Peñaranda committed
42

43 44 45 46 47 48 49 50
#define CONST_PI        3.141592653589793115997963468544185161590576171875
#define CONST_PI_2      1.5707963267948965579989817342720925807952880859375
#define CONST_PI_F      3.1415927410125732421875f
#define CONST_PI_2_F    1.57079637050628662109375f
//#define CONST_PI        (0x1.921fb54442d18p+1)
//#define CONST_PI_2      (0x1.921fb54442d18p+0)
//#define CONST_PI_F      (0x1.921fb6p+1f)
//#define CONST_PI_2_F    (0x1.921fb6p+0f)
Luis Peñaranda's avatar
Luis Peñaranda committed
51

Luis Peñaranda's avatar
Luis Peñaranda committed
52 53 54 55 56
OpenGLCanvas::OpenGLCanvas(QWidget *parent) :
    QGLWidget(parent)
{
    setFormat(QGL::DoubleBuffer | QGL::DepthBuffer);
    fov = 60.f;
Luis Peñaranda's avatar
Luis Peñaranda committed
57
    fov_max = 60.f; // TODO: I only use floats here because Leo did... check
Luis Peñaranda's avatar
Luis Peñaranda committed
58 59 60 61 62
    scale = 1.0f;
    center_lambda = 0.f;
    center_phi = 0.f;
    fov_scale_relation = "Square Root";
    visualization = "Perspective";
63
    auto_fov_max=false;
Luis Peñaranda's avatar
Luis Peñaranda committed
64 65 66 67 68 69 70 71 72 73 74 75 76

    time_frames = 0;
    time_timer.setInterval(0);
    connect(&time_timer, SIGNAL(timeout()), this, SLOT(slotTimer()));
    time_start = time_time.time();
}

void OpenGLCanvas::slotTimer(void) {
    updateGL();
}

void OpenGLCanvas::change_fov(double f){

Luis Peñaranda's avatar
Luis Peñaranda committed
77 78 79 80
    if (fov!=f && f>=1.f && f<=360.f)
        fov=f;
    if (fov<=fov_max)
        scale=1.f;
Luis Peñaranda's avatar
Luis Peñaranda committed
81 82
    //else if (fov>295.f)
    //    scale = 0.02f; // TODO: check this value wrt fov_max
Luis Peñaranda's avatar
Luis Peñaranda committed
83
    else {
Luis Peñaranda's avatar
Luis Peñaranda committed
84 85 86 87 88 89 90 91 92 93 94 95
        if (fov_scale_relation == "Naive")
            scale=fov_max/fov;
        else if (fov_scale_relation == "Square Root")
            scale=sqrt((360.f-fov_max-fov)/(360.-2*fov_max));
        else if (fov_scale_relation == "Linear")
            scale=(360.f-fov_max-fov)/(360.-2*fov_max);
        else if (fov_scale_relation == "Square Power")
            scale=powf((360.f-fov_max-fov)/(360.-2*fov_max),2);
        else if (fov_scale_relation == "Cubic Power")
            scale=powf((360.f-fov_max-fov)/(360.-2*fov_max),3);
        else if (fov_scale_relation == "Logarithm")
            scale=log(exp(1.f)+(1.f-exp(1.f))*(fov-fov_max)/(360.-2*fov_max));
Luis Peñaranda's avatar
Luis Peñaranda committed
96 97 98 99
    }

//    scale = 0.3f;

Luis Peñaranda's avatar
Luis Peñaranda committed
100
    fprintf(stderr,"change fov, fov=%f, fov_max=%f, scale=%f\n",fov,fov_max,scale);
101
    emit fov_changed((int)fov);
Luis Peñaranda's avatar
Luis Peñaranda committed
102

Luis Peñaranda's avatar
Luis Peñaranda committed
103 104 105 106
    updateGL();

}

107
void OpenGLCanvas::change_fov(int new_fov){
Luis Peñaranda's avatar
Luis Peñaranda committed
108 109
    if(new_fov<=360&&new_fov>=1)
            change_fov((double)new_fov);
110 111 112 113 114 115 116 117 118
    if(auto_fov_max){
        if(new_fov<60)
            change_fov_max(60);
        else
            if(new_fov>180)
                change_fov_max(1);
            else
                change_fov_max(90-new_fov/2);
    }
119 120 121
}

void OpenGLCanvas::change_fov_max(int new_fov_max){
Luis Peñaranda's avatar
Luis Peñaranda committed
122
    if(new_fov_max<=360&&new_fov_max>=1)
Luis Peñaranda's avatar
Luis Peñaranda committed
123
            fov_max=(double)new_fov_max;
124 125
    if (fov<=fov_max)
        scale=1.f;
Luis Peñaranda's avatar
Luis Peñaranda committed
126 127
    //else if (fov>295.f)
    //    scale = 0.02f; // TODO: check this value wrt fov_max
128 129 130 131 132 133 134 135 136 137 138 139 140 141
    else {
        if (fov_scale_relation == "Naive")
            scale=fov_max/fov;
        else if (fov_scale_relation == "Square Root")
            scale=sqrt((360.f-fov_max-fov)/(360.-2*fov_max));
        else if (fov_scale_relation == "Linear")
            scale=(360.f-fov_max-fov)/(360.-2*fov_max);
        else if (fov_scale_relation == "Square Power")
            scale=powf((360.f-fov_max-fov)/(360.-2*fov_max),2);
        else if (fov_scale_relation == "Cubic Power")
            scale=powf((360.f-fov_max-fov)/(360.-2*fov_max),3);
        else if (fov_scale_relation == "Logarithm")
            scale=log(exp(1.f)+(1.f-exp(1.f))*(fov-fov_max)/(360.-2*fov_max));
    }
Luis Peñaranda's avatar
Luis Peñaranda committed
142
    fprintf(stderr,"change fov_max, fov=%f, fov_max=%f, new scale=%f\n",fov,fov_max,scale);
143
    emit max_fov_changed((int)fov_max);
Luis Peñaranda's avatar
Luis Peñaranda committed
144 145 146
    updateGL();
}

Luis Peñaranda's avatar
Luis Peñaranda committed
147 148 149 150 151 152 153 154 155
//void OpenGLCanvas::change_scale(double s){

//    if (scale!=s && s>=0.0 && s<=1.0) scale = s;
//    updateGL();

//}

void OpenGLCanvas::change_center_lambda(double lambda){

Luis Peñaranda's avatar
Luis Peñaranda committed
156
    if (center_lambda!=lambda && lambda>=-CONST_PI && lambda<=CONST_PI) {
Luis Peñaranda's avatar
Luis Peñaranda committed
157 158 159 160 161 162 163 164
        center_lambda = lambda;
        updateGL();
    }

}

void OpenGLCanvas::change_center_phi(double phi){

Luis Peñaranda's avatar
Luis Peñaranda committed
165
    if (center_phi!=phi && phi>=-CONST_PI_2 && phi<=CONST_PI_2) {
Luis Peñaranda's avatar
Luis Peñaranda committed
166 167 168 169 170 171
        center_phi = phi;
        updateGL();
    }

}

Luis Peñaranda's avatar
Luis Peñaranda committed
172 173 174 175 176 177
void OpenGLCanvas::re_center(){
    center_phi=.0f;
    center_lambda=.0f;
    updateGL();
}

Luis Peñaranda's avatar
Luis Peñaranda committed
178 179 180
void OpenGLCanvas::change_fov_scale_relation(QString name){

   fov_scale_relation = name;
Luis Peñaranda's avatar
Luis Peñaranda committed
181 182
   if (fov<fov_max) scale = 1.f;
   //else if (fov>295.f) scale = 0.01f;
Luis Peñaranda's avatar
Luis Peñaranda committed
183
   else{
Luis Peñaranda's avatar
Luis Peñaranda committed
184 185 186 187 188 189 190 191 192 193 194 195
       if (fov_scale_relation == "Naive")
           scale=fov_max/fov;
       else if (fov_scale_relation == "Square Root")
           scale=sqrt((360.f-fov_max-fov)/(360.-2*fov_max));
       else if (fov_scale_relation == "Linear")
           scale=(360.f-fov_max-fov)/(360.-2*fov_max);
       else if (fov_scale_relation == "Square Power")
           scale=powf((360.f-fov_max-fov)/(360.-2*fov_max),2);
       else if (fov_scale_relation == "Cubic Power")
           scale=powf((360.f-fov_max-fov)/(360.-2*fov_max),3);
       else if (fov_scale_relation == "Logarithm")
           scale=log(exp(1.f)+(1.f-exp(1.f))*(fov-fov_max)/(360.-2*fov_max));
Luis Peñaranda's avatar
Luis Peñaranda committed
196
   }
197
   fprintf(stderr,"changed scale relation, scale=%f, fov_max=%f\n",scale,fov_max);
Luis Peñaranda's avatar
Luis Peñaranda committed
198 199 200 201 202 203 204
   updateGL();

}

void OpenGLCanvas::change_visualization(QString name){

    visualization = name;
205
    updateGL();
Luis Peñaranda's avatar
Luis Peñaranda committed
206 207 208

}

209 210 211
// This function reads the contents of the ~/.panorc file and stores the
// options in private variables.
void OpenGLCanvas::read_config_file(){
212
#ifdef _WIN32
Luis Penaranda's avatar
Luis Penaranda committed
213 214
    char* envvar=(char*)malloc(12*sizeof(char));
    strcpy(envvar,"USERPROFILE\0");
215
    char *filepath=(char*)malloc(512*sizeof(char));
Luis Penaranda's avatar
Luis Penaranda committed
216 217 218
    strcpy(filepath,getenv(envvar));
    free(envvar);
    strcat(filepath,"\\.panorc");
219
#else
220 221 222
    struct passwd *pw=getpwuid(getuid());
    char *filepath=pw->pw_dir;
    strcat(filepath,"/.panorc");
223
#endif
224 225 226 227
    shader_dir=(char*)malloc(512*sizeof(char));
    shader_dir[0]='\0';
    input_image_file=(char*)malloc(512*sizeof(char));
    input_image_file[0]='\0';
228
    char *read_line=(char*)malloc(64*sizeof(char));
229 230
    struct stat testbuf;
    if(stat(filepath,&testbuf)){
Luis Penaranda's avatar
Luis Penaranda committed
231
        fprintf(stderr,"%s does not exist\n",filepath);
232
    }else{
Luis Penaranda's avatar
Luis Penaranda committed
233 234
        FILE *rcfile;
        FOPEN_RO(rcfile,filepath);
235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258
        char c;
        char *line=(char*)malloc(512*sizeof(char));
        while((c=getc(rcfile))!=EOF){
            while(c=='\n') // discard empty lines
                c=getc(rcfile);
            if(c==EOF)
                break;
            line[0]=c; // first char on the line was already read
            if(!fgets(line+1,511,rcfile)){
                fprintf(stderr,"error reading rcfile\n");
                exit(-1);
            }
            // check for 'shader_dir' option
            if(!strncmp(line,"shader_dir=",11)){
                strcpy(shader_dir,line+11);
                shader_dir[strlen(line)-12]='\0';
                fprintf(stderr,"shader_dir=%s\n",shader_dir);
            }
            // check for 'image_file' option
            if(!strncmp(line,"image_file=",11)){
                strcpy(input_image_file,line+11);
                input_image_file[strlen(line)-12]='\0';
                fprintf(stderr,"input_image_file=%s\n",input_image_file);
            }
Luis Peñaranda's avatar
Luis Peñaranda committed
259 260
            // check for 'max_fov' option
            if(!strncmp(line,"max_fov=",8)){
261 262 263
                strcpy(read_line,line+8);
                read_line[strlen(line)-9]='\0';
                fov_max=atof(read_line);
Luis Peñaranda's avatar
Luis Peñaranda committed
264 265
                fprintf(stderr,"max_fov=%f\n",fov_max);
            }
266 267 268 269 270 271 272
            // check for 'auto_max_fov' option
            if(!strncmp(line,"auto_max_fov=",13)){
                strcpy(read_line,line+13);
                read_line[strlen(line)-14]='\0';
                auto_fov_max=atof(read_line);
                fprintf(stderr,"auto_max_fov=%d\n",auto_fov_max);
            }
273 274 275
        }
        fclose(rcfile);
    }
Luis Penaranda's avatar
Luis Penaranda committed
276 277 278
#ifdef _WIN32
    free(filepath);
#endif
Luis Peñaranda's avatar
Luis Peñaranda committed
279 280
    emit fov_changed((int)fov);
    emit max_fov_changed((int)fov_max);
281 282
}

283 284 285 286 287 288 289 290 291 292 293 294 295 296 297
void OpenGLCanvas::load_image(const char *new_image){
    const char * const progname=(char*)(PROGNAME);
    int textureSize=getTextureSize(progname,new_image);
    unsigned char * textureBytes=(unsigned char*)malloc(textureSize);
    int width,height;
    readTextureBytes(progname,new_image,textureBytes,&width,&height);
    glPixelStorei(GL_UNPACK_ALIGNMENT,1);
    GLuint tex;
    glGenTextures(1,&tex);
    glBindTexture(GL_TEXTURE_2D,tex);
    glTexParameteri(GL_TEXTURE_2D,GL_TEXTURE_MIN_FILTER,GL_LINEAR);
    glTexParameteri(GL_TEXTURE_2D,GL_TEXTURE_MAG_FILTER,GL_LINEAR);
    glTexImage2D(GL_TEXTURE_2D,0, GL_RGB, width,height,0,GL_RGB,GL_UNSIGNED_BYTE,textureBytes);
}

298
void OpenGLCanvas::change_input_image(){
299
    load_image(QFileDialog::getOpenFileName(this,tr("Choose Panorama File")).toStdString().c_str());
300 301 302
    updateGL();
}

Luis Peñaranda's avatar
Luis Peñaranda committed
303 304 305 306 307 308 309 310
void OpenGLCanvas::initializeGL(){
    glShadeModel(GL_SMOOTH);
    glClearColor(1.0f,1.0f,1.0f,0.0f);
    glClearDepth(1.0f);
    glEnable(GL_DEPTH_TEST);
    glDepthFunc(GL_LEQUAL);
    glHint(GL_PERSPECTIVE_CORRECTION_HINT,GL_NICEST);

311
#ifdef __APPLE__
Luis Peñaranda's avatar
Luis Peñaranda committed
312
    const char * const progname = "PROJ_ROOT_DIR";
313 314 315 316
#else
    // progname is a file name or a path???
    const char * const progname = (char*)(PROGNAME);
#endif
Luis Peñaranda's avatar
Luis Peñaranda committed
317

318
    fprintf(stderr,"progname=%s\n",progname);
319 320
    read_config_file();
    // If the input file does not exist or was not specified.
321
    struct stat testbuf;
322
    if(stat(input_image_file,&testbuf)||!strcmp(input_image_file,"")){
323 324
        load_image(QFileDialog::getOpenFileName(this,tr("Choose Panorama File")).toStdString().c_str());
    }else{
325
        load_image(input_image_file);
326
    }
327
    free(input_image_file);
Luis Peñaranda's avatar
Luis Peñaranda committed
328 329 330 331 332 333 334 335 336 337 338

    // mesh resolution
    int m,n;
    m = n = 100;

    //defining texture coordinates
    int meshNumTexCoord = m*n;
    float *texCoord = (float *)malloc(2*meshNumTexCoord*sizeof(float));
    if (texCoord == NULL){
        printf("problem allocating memory for texture coordinates \n");
    }
Luis Peñaranda's avatar
Luis Peñaranda committed
339
    define_texture_coordinates(texCoord, m, n, -CONST_PI_2_F, CONST_PI_2_F, -CONST_PI_F, CONST_PI_F);
Luis Peñaranda's avatar
Luis Peñaranda committed
340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371

    //defining positions of the sphere vertices
    int meshNumVertices = m*n;
    float* positions = (float *)malloc(3*meshNumVertices*sizeof(float));
    if (positions == NULL){
        printf("problem allocating memory for positions \n");
    }
//    vertex_transformation(positions, m, n, center_lambda, center_phi, fov_rads, scale); //passar pelo vertex shader
    load_sphere_mesh(positions, m, n); //colocar essa e funcoes para textura e triangulos no initializeGL

    //defining triagle indices
    unsigned int meshNumFaces = 2*(m-1)*(n-1);
    unsigned int meshNumIndices = 3*meshNumFaces;
    unsigned int * indices = (unsigned int *)malloc(meshNumIndices*sizeof(unsigned int));
    define_triangle_indices(indices, m, n);

    // draw setup
    verticesPositions = positions;
    textureCoordinates = texCoord;
    numberOfIndices = meshNumIndices;
    triangleIndices = indices;

    setShaders();
}

void OpenGLCanvas::define_texture_coordinates(float *texCoord, int m, int n, float min_phi, float max_phi, float min_lambda, float max_lambda){

    float delta_lambda = (max_lambda-min_lambda)/(1.0*(n-1));
    float delta_phi = (max_phi-min_phi)/(1.0*(m-1));

    for (int i = 0; i<m; i++){
        for (int j = 0; j<n; j++){
Luis Peñaranda's avatar
Luis Peñaranda committed
372 373
            texCoord[2*(j+i*n)] = (min_lambda+delta_lambda*j)/(2*CONST_PI_F) + 0.5;
            texCoord[2*(j+i*n)+1] = (min_phi+delta_phi*i)/(CONST_PI_F) + 0.5;
Luis Peñaranda's avatar
Luis Peñaranda committed
374 375 376 377 378 379 380
        }
    }

}

void OpenGLCanvas::vertex_transformation(float *positions, int m, int n, float center_lambda, float center_phi, float fov_rads, float scale){

Luis Peñaranda's avatar
Luis Peñaranda committed
381 382 383 384
    float min_lambda = -CONST_PI_F;
    float max_lambda = CONST_PI_F;
    float min_phi = -CONST_PI_2_F;
    float max_phi = CONST_PI_2_F;
Luis Peñaranda's avatar
Luis Peñaranda committed
385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451

    float delta_lambda = (max_lambda-min_lambda)/(1.0*(n-1));
    float delta_phi = (max_phi-min_phi)/(1.0*(m-1));

    float lambda, phi, x, y, z, u, v, r, theta;

    //calculating the extent of the projection for the given FOV
    lambda = fov_rads;
    phi = 0.f;
    // OpenGL: x is the vertical axes pointg downwards, and y is horizontal axes
    y = sin(phi);
    x = -sin(lambda)*cos(phi);
    z = -cos(lambda)*cos(phi);
    u = 2.f*x/(-z+1.f);
    v = 2.f*y/(-z+1.f);
    r = sqrt(u*u+v*v);
    theta = atan2(u,v);
    r *= scale;
    u = -r*sin(theta);
    v = r*cos(theta);
    x = (4.f*u)/(u*u+v*v+4.f);
    y = (4.f*v)/(u*u+v*v+4.f);
    z = (u*u+v*v-4.f)/(u*u+v*v+4.f);
    u = x/(-z);
    v = y/(-z);
    float extent = u;

    for (int i = 0; i<m; i++){
        for (int j = 0; j<n; j++){

            lambda = (min_lambda+delta_lambda*j);
            phi = (min_phi+delta_phi*i);

            // OpenGL: x is the vertical axes pointg downwards, and y is horizontal axes
            y = sin(phi);
            x = -sin(lambda)*cos(phi);
            z = -cos(lambda)*cos(phi);

            //Rotation 1: (-center_lambda)-rotation on the xz-plane
            float x_copy = x;
            x = cos(-center_lambda)*x - sin(-center_lambda)*z;
            y = 1.f*y;
            z = sin(-center_lambda)*x_copy + cos(-center_lambda)*z;

            //Rotation 2: (-center_phi)-rotation on the yz-plane
            float y_copy = y;
            x = 1.f*x;
            y = cos(-center_phi)*y - sin(-center_phi)*z;
            z = sin(-center_phi)*y_copy + cos(-center_phi)*z;


            u = 2.f*x/(-z+1.f);
            v = 2.f*y/(-z+1.f);

            r = sqrt(u*u+v*v);
            theta = atan2(u,v);

            // scaling the complex plane according to scale specified in the interface (relate it to FOV)
            r *= scale;

            u = -r*sin(theta);
            v = r*cos(theta);

            x = (4.f*u)/(u*u+v*v+4.f);
            y = (4.f*v)/(u*u+v*v+4.f);
            z = (u*u+v*v-4.f)/(u*u+v*v+4.f);

Luis Peñaranda's avatar
Luis Peñaranda committed
452 453
            lambda = atan2(x,-z)/CONST_PI_F;
            phi = asin(y)/CONST_PI_2_F;
Luis Peñaranda's avatar
Luis Peñaranda committed
454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482

            u = x/(-z);
            v = y/(-z);

            if (visualization=="Perspective"){
                positions[3*(j+i*n)] = u/extent;
                positions[3*(j+i*n)+1] = v/extent;
                positions[3*(j+i*n)+2] = z;
            }

            if (visualization=="3D Sphere"){
                positions[3*(j+i*n)] = 0.9f*x;
                positions[3*(j+i*n)+1] = 0.9f*y;
                positions[3*(j+i*n)+2] = z;
            }

            if (visualization=="Equi-Rectangular"){
                positions[3*(j+i*n)] = lambda;
                positions[3*(j+i*n)+1] = phi;
                positions[3*(j+i*n)+2] = z;
            }

        }
    }

}

void OpenGLCanvas::load_sphere_mesh(float *positions, int m, int n){

Luis Peñaranda's avatar
Luis Peñaranda committed
483 484 485 486
    float min_lambda = -CONST_PI_F;
    float max_lambda = CONST_PI_F;
    float min_phi = -CONST_PI_2_F;
    float max_phi = CONST_PI_2_F;
Luis Peñaranda's avatar
Luis Peñaranda committed
487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514

    float delta_lambda = (max_lambda-min_lambda)/(1.0*(n-1));
    float delta_phi = (max_phi-min_phi)/(1.0*(m-1));

    float lambda, phi, x, y, z;

    for (int i = 0; i<m; i++){
        for (int j = 0; j<n; j++){

            lambda = (min_lambda+delta_lambda*j);
            phi = (min_phi+delta_phi*i);

            // OpenGL: x is the vertical axes pointg downwards, and y is horizontal axes
            y = sin(phi);
            x = -sin(lambda)*cos(phi);
            z = -cos(lambda)*cos(phi);

            positions[3*(j+i*n)] = x;
            positions[3*(j+i*n)+1] = y;
            positions[3*(j+i*n)+2] = z;

        }
    }

}

float OpenGLCanvas::calculate_extent(float fov_rads){

Luis Peñaranda's avatar
Luis Peñaranda committed
515
    double lambda, phi, x, y, z, u, v, r, theta;
Luis Peñaranda's avatar
Luis Peñaranda committed
516 517
    //calculating the extent of the projection for the given FOV
    lambda = fov_rads;
Luis Peñaranda's avatar
Luis Peñaranda committed
518
    phi = 0.;
Luis Peñaranda's avatar
Luis Peñaranda committed
519 520 521 522
    // OpenGL: x is the vertical axes pointg downwards, and y is horizontal axes
    y = sin(phi);
    x = -sin(lambda)*cos(phi);
    z = -cos(lambda)*cos(phi);
Luis Peñaranda's avatar
Luis Peñaranda committed
523 524
    u = 2.*x/(-z+1.);
    v = 2.*y/(-z+1.);
Luis Peñaranda's avatar
Luis Peñaranda committed
525 526 527 528 529
    r = sqrt(u*u+v*v);
    theta = atan2(u,v);
    r *= scale;
    u = -r*sin(theta);
    v = r*cos(theta);
Luis Peñaranda's avatar
Luis Peñaranda committed
530 531 532
    x = (4.*u)/(u*u+v*v+4.);
    y = (4.*v)/(u*u+v*v+4.);
    z = (u*u+v*v-4.)/(u*u+v*v+4.);
Luis Peñaranda's avatar
Luis Peñaranda committed
533 534 535 536 537 538 539 540 541 542 543 544 545 546 547 548 549 550 551 552 553 554 555 556 557 558 559 560
    u = x/(-z);
    v = y/(-z);
    return u;
}

void OpenGLCanvas::define_triangle_indices(unsigned int * indices, int m, int n){

    for (int i = 0; i<m-1; i++){
        for (int j = 0; j<n-1; j++){

            unsigned int index = (j+i*n);

            indices[3*(2*(j+i*(n-1)))] = index;
            indices[3*(2*(j+i*(n-1)))+1] = index+1;
            indices[3*(2*(j+i*(n-1)))+2] = index+n;

            indices[3*(2*(j+i*(n-1))+1)] = index+1;
            indices[3*(2*(j+i*(n-1))+1)+1] = index+n+1;
            indices[3*(2*(j+i*(n-1))+1)+2] = index+n;

        }
    }

}

int OpenGLCanvas::getTextureSize(const char * const progname, const char * texturePath)
{
    struct pam inpam;
561
    pm_init(progname, 0);
Luis Penaranda's avatar
Luis Penaranda committed
562 563
    FILE *in_file;
    FOPEN_RO(in_file,texturePath)
Luis Peñaranda's avatar
Luis Peñaranda committed
564

565 566 567 568 569
#ifdef PAM_STRUCT_SIZE
    pnm_readpaminit(in_file,&inpam,PAM_STRUCT_SIZE(tuple_type));
#else
    pnm_readpaminit(in_file,&inpam,sizeof(struct pam));
#endif
Luis Peñaranda's avatar
Luis Peñaranda committed
570

Luis Peñaranda's avatar
Luis Peñaranda committed
571 572 573
    image_size_x=inpam.width;
    image_size_y=inpam.height;
    int size = image_size_x*image_size_y*inpam.depth*inpam.bytes_per_sample;
574
    pm_close(in_file);
Luis Peñaranda's avatar
Luis Peñaranda committed
575

576 577
    //fprintf(stderr,"size=%d\n",size);
    return size;
Luis Peñaranda's avatar
Luis Peñaranda committed
578 579 580 581 582 583 584 585 586 587 588 589 590
}

void OpenGLCanvas::readTextureBytes(const char * const progname,
                                          const char * texturePath,
                                          unsigned char * textureBytes,
                                          int * outImageWidth,
                                          int * outImageHeight)
{
        struct pam inpam;
        tuple * tuplerow;
        int row;

        pm_init(progname, 0);
Luis Penaranda's avatar
Luis Penaranda committed
591 592
        FILE *in_file;
        FOPEN_RO(in_file,texturePath);
Luis Peñaranda's avatar
Luis Peñaranda committed
593

594 595 596 597 598
#ifdef PAM_STRUCT_SIZE
        pnm_readpaminit(in_file,&inpam,PAM_STRUCT_SIZE(tuple_type));
#else
        pnm_readpaminit(in_file,&inpam,sizeof(struct pam));
#endif
Luis Peñaranda's avatar
Luis Peñaranda committed
599 600 601 602 603 604 605 606 607 608 609 610 611 612 613 614 615 616 617 618 619 620 621

        tuplerow = pnm_allocpamrow(&inpam);

        for (row = 0; row < inpam.height; row++) {
                int column;
                pnm_readpamrow(&inpam, tuplerow);
                for (column = 0; column < inpam.width; ++column) {
                        unsigned int plane;
                        for (plane = 0; plane < inpam.depth; ++plane) {
                                textureBytes[(inpam.height-row-1)*3*inpam.width+3*column+plane] = tuplerow[column][plane];
                        }
                }
        }

        pnm_freepamrow(tuplerow);

        *outImageWidth = inpam.width;
        *outImageHeight = inpam.height;

        pm_close(in_file);
}

void OpenGLCanvas::resizeGL(int w, int h){
622 623 624 625
    if(w>h)
        glViewport(0,(h-w)/2,w,w);
    else
        glViewport((w-h)/2,0,h,h);
Luis Peñaranda's avatar
Luis Peñaranda committed
626 627 628 629 630 631 632
}

char * OpenGLCanvas::textFileRead(char *fn) {

    FILE *fp;
    char *content = NULL;
    int f, count;
633 634
    f = OPEN_FILE(fn, O_RDONLY);
    count = LSEEK_FD(f, 0, SEEK_END);
Luis Peñaranda's avatar
Luis Peñaranda committed
635 636
//    close(f);
    if (fn != NULL) {
Luis Penaranda's avatar
Luis Penaranda committed
637 638
        //fp = fopen(fn,"rt");
        FOPEN_RO(fp,fn);
Luis Peñaranda's avatar
Luis Peñaranda committed
639 640 641 642 643 644
        if (fp != NULL) {
            if (count > 0) {
                content = (char *)malloc(sizeof(char) * (count+1));
                count = fread(content,sizeof(char),count,fp);
                content[count] = '\0';
            }
Luis Penaranda's avatar
Luis Penaranda committed
645
            fclose(fp); // maybe this line must be outside the {}
Luis Peñaranda's avatar
Luis Peñaranda committed
646 647 648 649 650 651 652 653 654
        }
    }
    return content;
}

void OpenGLCanvas::setShaders() {

    char *vs,*fs;

Luis Peñaranda's avatar
Luis Peñaranda committed
655 656
#ifndef __APPLE__
  #ifdef GLEW_VERSION_1_5
657 658 659 660 661
    GLenum err=glewInit();
    if(err!=GLEW_OK){
        fprintf(stderr,"error in GLEW initialization: %s\n",glewGetString(err));
        exit(-1);
    }
Luis Peñaranda's avatar
Luis Peñaranda committed
662
  #endif
663 664
#endif

Luis Peñaranda's avatar
Luis Peñaranda committed
665 666 667
    GLuint v = glCreateShader(GL_VERTEX_SHADER);
    GLuint f = glCreateShader(GL_FRAGMENT_SHADER);

668
    // Configure vertex and fragment shader files.
669 670
    char *vs_file=(char*)malloc(512*sizeof(char*));
    char *fs_file=(char*)malloc(512*sizeof(char*));
671 672 673 674 675 676 677 678 679 680 681 682 683 684
    if(!strcmp(shader_dir,"")){ // if shader_dir was not configured
        if(!GET_WORKDIR(vs_file,512)||!GET_WORKDIR(fs_file,512)){
            fprintf(stderr,"error reading shader files\n");
            exit(-1);
        }
        strcat(vs_file,"/shaders/");
        strcat(fs_file,"/shaders/");
    }else{;
        strcpy(vs_file,shader_dir);
        strcat(vs_file,"/");
        strcpy(fs_file,shader_dir);
        strcat(fs_file,"/");
    }
    strcat(vs_file,VERT_SHADER_FILE);
685
    strcat(fs_file,FRAG_SHADER_FILE);
686
    fprintf(stderr,"vs_file=%s\nfs_file=%s\n",vs_file,fs_file);
687 688 689 690 691 692 693 694

    struct stat vs_testbuf,fs_testbuf;
    if(stat(vs_file,&vs_testbuf)||stat(fs_file,&fs_testbuf)){
        fprintf(stderr,"a shader file does not exist!\n");
        free(vs_file);
        free(fs_file);
        exit(-1);
    }
Luis Peñaranda's avatar
Luis Peñaranda committed
695

696 697
    vs=textFileRead(vs_file);
    fs=textFileRead(fs_file);
Luis Peñaranda's avatar
Luis Peñaranda committed
698 699 700 701 702 703 704 705

    const char * vv = vs;
    const char * ff = fs;

    glShaderSource(v, 1, &vv,NULL);
    glShaderSource(f, 1, &ff,NULL);

    free(vs);free(fs);
706
    free(vs_file);free(fs_file);
Luis Peñaranda's avatar
Luis Peñaranda committed
707 708 709 710 711 712 713 714 715 716 717 718 719 720

    glCompileShader(v);
    glCompileShader(f);

    GLuint p = glCreateProgram();

    glAttachShader(p,v);
    glAttachShader(p,f);

    glLinkProgram(p);
    glUseProgram(p);

}

Luis Peñaranda's avatar
Luis Peñaranda committed
721 722 723 724 725 726 727 728 729
void OpenGLCanvas::mousePressEvent(QMouseEvent *event){
    lastPos=event->pos();
    //fprintf(stderr,"mouse click\n");
}

void OpenGLCanvas::mouseMoveEvent(QMouseEvent *event){
    // scroll with the left button
    if(event->buttons()==Qt::LeftButton){
        // compute the delta and move the image
Luis Peñaranda's avatar
Luis Peñaranda committed
730 731
        center_lambda+=(event->x()-lastPos.x())*CONST_PI_F/image_size_x;
        center_phi+=(event->y()-lastPos.y())*CONST_PI_F/image_size_y;
Luis Peñaranda's avatar
Luis Peñaranda committed
732 733 734 735 736
        lastPos=event->pos();
        updateGL();
    }
}

737 738
void OpenGLCanvas::wheelEvent(QWheelEvent *event){
    if(event->orientation()==Qt::Vertical){
739
        if(event->modifiers()==Qt::ShiftModifier){
740 741
            change_fov_max(fov_max+((double)event->delta())/30);
        }else{
742 743 744 745 746 747 748 749 750 751 752
            int new_fov=fov+event->delta()/30;
            change_fov((double)new_fov);
            if(auto_fov_max){
                if(new_fov<60)
                    change_fov_max(60);
                else
                    if(new_fov>180)
                        change_fov_max(1);
                    else
                        change_fov_max(90-new_fov/2);
            }
753
        }
754 755 756
    }
}

Luis Peñaranda's avatar
Luis Peñaranda committed
757 758
void OpenGLCanvas::paintGL(){

Luis Peñaranda's avatar
Luis Peñaranda committed
759
    float fov_rads = (fov/360.)*CONST_PI;
Luis Peñaranda's avatar
Luis Peñaranda committed
760 761 762 763 764 765 766

//    // changing scale to generate the figures for the paper (remove it after)
//    scale = 0.8;


    // defining transformation parameters (that will be passed to the vertex shader)
    float extent = calculate_extent(fov_rads);
Luis Penaranda's avatar
Luis Penaranda committed
767
    float vis_mode=.0;
Luis Peñaranda's avatar
Luis Peñaranda committed
768 769 770 771 772 773 774 775 776 777 778 779 780 781 782 783 784 785 786 787 788 789 790 791 792 793 794 795 796 797 798 799 800 801 802 803
    if (visualization=="Perspective") vis_mode=1.0;
    else if (visualization=="3D Sphere") vis_mode=2.0;
    else if (visualization=="Equi-Rectangular") vis_mode=3.0;
    glMatrixMode(GL_PROJECTION);
    glLoadIdentity();
    glOrtho(0.0, 2.0/extent, 0.0, 2.0/scale, 0.0, -2.0/vis_mode);

    glMatrixMode(GL_MODELVIEW);
    glLoadIdentity();
    glOrtho(0.0, 2.0/center_lambda, 0.0, 2.0/center_phi, -1.0, 1.0);

    // drawing the mesh
    glClearColor(1.0, 1.0, 1.0, 1.0);

    glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
    glEnable(GL_TEXTURE_2D);
    glTexEnvf(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_REPLACE);

    glColor3f(1, 0, 0);

    glEnableClientState(GL_VERTEX_ARRAY);
    glVertexPointer(3, GL_FLOAT, 0, verticesPositions);
    glEnableClientState(GL_TEXTURE_COORD_ARRAY);
    glTexCoordPointer(2, GL_FLOAT, 0, textureCoordinates);

    glDrawElements(GL_TRIANGLES, numberOfIndices, GL_UNSIGNED_INT, triangleIndices);
    glDisableClientState(GL_TEXTURE_COORD_ARRAY);
    glDisableClientState(GL_VERTEX_ARRAY);

    time_frames++;
//    if (time_frames > 0) {
        double dt = time_time.elapsed();
//        if (dt > 0.5) {
            time_fps = time_frames/dt;
            time_frames = 0;
            time_time.reset();
Luis Peñaranda's avatar
Luis Peñaranda committed
804 805
            emit fps(QString("%1 fps").arg((int)(time_fps+0.5)));
            //printf("fps = %d ", (int)(time_fps+0.5));
Luis Peñaranda's avatar
Luis Peñaranda committed
806 807 808 809
//        }
//    }

}