src/zgl.h

   1 #ifndef _tgl_zgl_h_
   2 #define _tgl_zgl_h_
   3
   4 #include <stdlib.h>
   5 #include <stdio.h>
   6 #include <math.h>
   7 #include <assert.h>
   8 #include <GL/gl.h>
   9 #include "zbuffer.h"
  10 #include "zmath.h"
  11 #include "zfeatures.h"
  12
  13 #define DEBUG
  14 /* #define NDEBUG */
  15
  16 enum {
  17
  18 #define ADD_OP(a,b,c) OP_ ## a ,
  19
  20 #include "opinfo.h"
  21
  22 };
  23
  24 /* initially # of allocated GLVertexes (will grow when necessary) */
  25 #define POLYGON_MAX_VERTEX 16
  26
  27 /* Max # of specular light pow buffers */
  28 #define MAX_SPECULAR_BUFFERS 8
  29 /* # of entries in specular buffer */
  30 #define SPECULAR_BUFFER_SIZE 1024
  31 /* specular buffer granularity */
  32 #define SPECULAR_BUFFER_RESOLUTION 1024
  33
  34
  35 #define MAX_MODELVIEW_STACK_DEPTH  32
  36 #define MAX_PROJECTION_STACK_DEPTH 8
  37 #define MAX_TEXTURE_STACK_DEPTH    8
  38 #define MAX_NAME_STACK_DEPTH       64
  39 #define MAX_TEXTURE_LEVELS         11
  40 #define MAX_LIGHTS                 16
  41
  42 #define VERTEX_HASH_SIZE 1031
  43
  44 #define MAX_DISPLAY_LISTS 1024
  45 #define OP_BUFFER_MAX_SIZE 512
  46
  47 #define TGL_OFFSET_FILL    0x1
  48 #define TGL_OFFSET_LINE    0x2
  49 #define TGL_OFFSET_POINT   0x4
  50
  51 typedef struct GLSpecBuf {
  52         int shininess_i;
  53         int last_used;
  54         float buf[SPECULAR_BUFFER_SIZE+1];
  55         struct GLSpecBuf *next;
  56 } GLSpecBuf;
  57
  58 typedef struct GLLight {
  59         V4 ambient;
  60         V4 diffuse;
  61         V4 specular;
  62         V4 position;
  63         V3 spot_direction;
  64         float spot_exponent;
  65         float spot_cutoff;
  66         float attenuation[3];
  67         /* precomputed values */
  68         float cos_spot_cutoff;
  69         V3 norm_spot_direction;
  70         V3 norm_position;
  71         /* we use a linked list to know which are the enabled lights */
  72         int enabled;
  73         struct GLLight *next,*prev;
  74 } GLLight;
  75
  76 typedef struct GLMaterial {
  77         V4 emission;
  78         V4 ambient;
  79         V4 diffuse;
  80         V4 specular;
  81         float shininess;
  82
  83         /* computed values */
  84         int shininess_i;
  85         int do_specular;
  86 } GLMaterial;
  87
  88
  89 typedef struct GLViewport {
  90         int xmin,ymin,xsize,ysize;
  91         V3 scale;
  92         V3 trans;
  93         int updated;
  94 } GLViewport;
  95
  96 typedef union {
  97         int op;
  98         float f;
  99         int i;
 100         unsigned int ui;
 101         void *p;
 102 } GLParam;
 103
 104 typedef struct GLParamBuffer {
 105         GLParam ops[OP_BUFFER_MAX_SIZE];
 106         struct GLParamBuffer *next;
 107 } GLParamBuffer;
 108
 109 typedef struct GLList {
 110         GLParamBuffer *first_op_buffer;
 111         /* TODO: extensions for an hash table or a better allocating scheme */
 112 } GLList;
 113
 114 typedef struct GLVertex {
 115         int edge_flag;
 116         V3 normal;
 117         V4 coord;
 118         V4 tex_coord;
 119         V4 color;
 120
 121         /* computed values */
 122         V4 ec;                /* eye coordinates */
 123         V4 pc;                /* coordinates in the normalized volume */
 124         int clip_code;        /* clip code */
 125         ZBufferPoint zp;      /* integer coordinates for the rasterization */
 126 } GLVertex;
 127
 128 typedef struct GLImage {
 129         void *pixmap;
 130         int xsize,ysize;
 131 } GLImage;
 132
 133 /* textures */
 134
 135 #define TEXTURE_HASH_TABLE_SIZE 256
 136
 137 typedef struct GLTexture {
 138         GLImage images[MAX_TEXTURE_LEVELS];
 139         int handle;
 140         struct GLTexture *next,*prev;
 141 } GLTexture;
 142
 143
 144 /* shared state */
 145
 146 typedef struct GLSharedState {
 147         GLList **lists;
 148         GLTexture **texture_hash_table;
 149 } GLSharedState;
 150
 151 struct GLContext;
 152
 153 typedef void (*gl_draw_triangle_func)(struct GLContext *c,
 154                 GLVertex *p0,GLVertex *p1,GLVertex *p2);
 155
 156 /* display context */
 157
 158 typedef struct GLContext {
 159         /* Z buffer */
 160         ZBuffer *zb;
 161
 162         /* lights */
 163         GLLight lights[MAX_LIGHTS];
 164         GLLight *first_light;
 165         V4 ambient_light_model;
 166         int local_light_model;
 167         int lighting_enabled;
 168         int light_model_two_side;
 169
 170         /* materials */
 171         GLMaterial materials[2];
 172         int color_material_enabled;
 173         int current_color_material_mode;
 174         int current_color_material_type;
 175
 176         /* textures */
 177         GLTexture *current_texture;
 178         int texture_2d_enabled;
 179
 180         /* shared state */
 181         GLSharedState shared_state;
 182
 183         /* current list */
 184         GLParamBuffer *current_op_buffer;
 185         int current_op_buffer_index;
 186         int exec_flag,compile_flag,print_flag;
 187
 188         /* matrix */
 189
 190         int matrix_mode;
 191         M4 *matrix_stack[3];
 192         M4 *matrix_stack_ptr[3];
 193         int matrix_stack_depth_max[3];
 194
 195         M4 matrix_model_view_inv;
 196         M4 matrix_model_projection;
 197         int matrix_model_projection_updated;
 198         int matrix_model_projection_no_w_transform;
 199         int apply_texture_matrix;
 200
 201         /* viewport */
 202         GLViewport viewport;
 203
 204         /* current state */
 205         int polygon_mode_back;
 206         int polygon_mode_front;
 207
 208         int current_front_face;
 209         int current_shade_model;
 210         int current_cull_face;
 211         int cull_face_enabled;
 212         int normalize_enabled;
 213         gl_draw_triangle_func draw_triangle_front,draw_triangle_back;
 214
 215         /* selection */
 216         int render_mode;
 217         unsigned int *select_buffer;
 218         int select_size;
 219         unsigned int *select_ptr,*select_hit;
 220         int select_overflow;
 221         int select_hits;
 222
 223         /* names */
 224         unsigned int name_stack[MAX_NAME_STACK_DEPTH];
 225         int name_stack_size;
 226
 227         /* clear */
 228         float clear_depth;
 229         V4 clear_color;
 230
 231         /* current vertex state */
 232         V4 current_color;
 233         unsigned int longcurrent_color[3]; /* precomputed integer color */
 234         V4 current_normal;
 235         V4 current_tex_coord;
 236         int current_edge_flag;
 237
 238         /* glBegin / glEnd */
 239         int in_begin;
 240         int begin_type;
 241         int vertex_n,vertex_cnt;
 242         int vertex_max;
 243         GLVertex *vertex;
 244
 245         /* opengl 1.1 arrays  */
 246         float *vertex_array;
 247         int vertex_array_size;
 248         int vertex_array_stride;
 249         float *normal_array;
 250         int normal_array_stride;
 251         float *color_array;
 252         int color_array_size;
 253         int color_array_stride;
 254         float *texcoord_array;
 255         int texcoord_array_size;
 256         int texcoord_array_stride;
 257         int client_states;
 258
 259         /* opengl 1.1 polygon offset */
 260         float offset_factor;
 261         float offset_units;
 262         int offset_states;
 263
 264         /* specular buffer. could probably be shared between contexts,
 265            but that wouldn't be 100% thread safe */
 266         GLSpecBuf *specbuf_first;
 267         int specbuf_used_counter;
 268         int specbuf_num_buffers;
 269
 270         /* opaque structure for user's use */
 271         void *opaque;
 272         /* resize viewport function */
 273         int (*gl_resize_viewport)(struct GLContext *c,int *xsize,int *ysize);
 274
 275         /* depth test */
 276         int depth_test;
 277 } GLContext;
 278
 279 extern GLContext *gl_ctx;
 280
 281 void gl_add_op(GLParam *p);
 282
 283 /* clip.c */
 284 void gl_transform_to_viewport(GLContext *c,GLVertex *v);
 285 void gl_draw_triangle(GLContext *c,GLVertex *p0,GLVertex *p1,GLVertex *p2);
 286 void gl_draw_line(GLContext *c,GLVertex *p0,GLVertex *p1);
 287 void gl_draw_point(GLContext *c,GLVertex *p0);
 288
 289 void gl_draw_triangle_point(GLContext *c,
 290                 GLVertex *p0,GLVertex *p1,GLVertex *p2);
 291 void gl_draw_triangle_line(GLContext *c,
 292                 GLVertex *p0,GLVertex *p1,GLVertex *p2);
 293 void gl_draw_triangle_fill(GLContext *c,
 294                 GLVertex *p0,GLVertex *p1,GLVertex *p2);
 295 void gl_draw_triangle_select(GLContext *c,
 296                 GLVertex *p0,GLVertex *p1,GLVertex *p2);
 297
 298 /* matrix.c */
 299 void gl_print_matrix(const float *m);
 300 /*
 301    void glopLoadIdentity(GLContext *c,GLParam *p);
 302    void glopTranslate(GLContext *c,GLParam *p);*/
 303
 304 /* light.c */
 305 void gl_add_select(GLContext *c,unsigned int zmin,unsigned int zmax);
 306 void gl_enable_disable_light(GLContext *c,int light,int v);
 307 void gl_shade_vertex(GLContext *c,GLVertex *v);
 308
 309 void glInitTextures(GLContext *c);
 310 void glEndTextures(GLContext *c);
 311 GLTexture *alloc_texture(GLContext *c,int h);
 312
 313 /* image_util.c */
 314 void gl_convertRGB_to_5R6G5B(unsigned short *pixmap,unsigned char *rgb,
 315                 int xsize,int ysize);
 316 void gl_convertRGB_to_8A8R8G8B(unsigned int *pixmap, unsigned char *rgb,
 317                 int xsize, int ysize);
 318 void gl_resizeImage(unsigned char *dest,int xsize_dest,int ysize_dest,
 319                 unsigned char *src,int xsize_src,int ysize_src);
 320 void gl_resizeImageNoInterpolate(unsigned char *dest,int xsize_dest,int ysize_dest,
 321                 unsigned char *src,int xsize_src,int ysize_src);
 322
 323 GLContext *gl_get_context(void);
 324
 325 void gl_fatal_error(char *format, ...);
 326
 327
 328 /* specular buffer "api" */
 329 GLSpecBuf *specbuf_get_buffer(GLContext *c, const int shininess_i,
 330                 const float shininess);
 331
 332 #ifdef __BEOS__
 333 void dprintf(const char *, ...);
 334
 335 #else /* !BEOS */
 336
 337 #ifdef DEBUG
 338
 339 #define dprintf(format, args...)  \
 340         fprintf(stderr,"In '%s': " format "\n",__FUNCTION__, ##args);
 341
 342 #else
 343
 344 #define dprintf(format, args...)
 345
 346 #endif
 347 #endif /* !BEOS */
 348
 349 /* glopXXX functions */
 350
 351 #define ADD_OP(a,b,c) void glop ## a (GLContext *,GLParam *);
 352 #include "opinfo.h"
 353
 354 /* this clip epsilon is needed to avoid some rounding errors after
 355    several clipping stages */
 356
 357 #define CLIP_EPSILON (1E-5)
 358
 359 static inline int gl_clipcode(float x,float y,float z,float w1)
 360 {
 361         float w;
 362
 363         w=w1 * (1.0 + CLIP_EPSILON);
 364         return (x<-w) |
 365                 ((x>w)<<1) |
 366                 ((y<-w)<<2) |
 367                 ((y>w)<<3) |
 368                 ((z<-w)<<4) |
 369                 ((z>w)<<5) ;
 370 }
 371
 372 #endif /* _tgl_zgl_h_ */