pointcloud.h

   1 #ifndef POINTCLOUD_H
   2 #define POINTCLOUD_H
   3
   4 #include "common.h"
   5 #include "world.h"
   6 #include "shaders/point_map.h"
   7
   8 #define POINTCLOUD_POINTS 250000
   9
  10 struct pointcloud{
  11    GLuint vao, vbo;
  12    u32 count;
  13
  14    f64 anim_start;
  15    f32 visibility;
  16    enum pointcloud_anim{
  17       k_pointcloud_anim_opening,
  18       k_pointcloud_anim_hiding,
  19       k_pointcloud_anim_idle_any,
  20       k_pointcloud_anim_idle_open,
  21       k_pointcloud_anim_idle_closed,
  22    }
  23    anim;
  24 }
  25 static pointcloud;
  26
  27 #pragma pack(push,1)
  28 struct pointcloud_vert{
  29    i16 pos[4];    /* float[ -1 -> 1 ] */
  30    u8  colour[4]; /* float[  0 -> 1 ] */
  31 };
  32 #pragma pack(pop)
  33
  34 typedef struct pointcloud_vert pointcloud_vert;
  35 typedef struct pointcloud_buffer pointcloud_buffer;
  36
  37 struct pointcloud_buffer{
  38    u32 max, count;
  39    boxf boundary;
  40
  41    enum pointcloud_op{
  42       k_pointcloud_op_clear,
  43       k_pointcloud_op_append
  44    }
  45    op;
  46    pointcloud_vert buf[];
  47 };
  48
  49 static void async_pointcloud_sub( void *payload, u32 size ){
  50    glBindVertexArray( pointcloud.vao );
  51    glBindBuffer( GL_ARRAY_BUFFER, pointcloud.vbo );
  52
  53    pointcloud_buffer *buf = payload;
  54
  55    u32 start,end,count;
  56    if( buf->op == k_pointcloud_op_append ){
  57       start = pointcloud.count;
  58       end = pointcloud.count + buf->count;
  59    }
  60    else{
  61       start = 0;
  62       end = buf->count;
  63    }
  64
  65    end = VG_MIN(POINTCLOUD_POINTS,end);
  66    count = end-start;
  67
  68    if( count ){
  69       u32 size   = count * sizeof(pointcloud_vert),
  70           offset = start * sizeof(pointcloud_vert);
  71
  72       glBufferSubData( GL_ARRAY_BUFFER, offset, size, buf->buf );
  73       pointcloud.count = end;
  74    }
  75 }
  76
  77 static void async_pointcloud_alloc( void *payload, u32 size ){
  78    glGenVertexArrays( 1, &pointcloud.vao );
  79    glGenBuffers( 1, &pointcloud.vbo );
  80    glBindVertexArray( pointcloud.vao );
  81
  82    size_t stride = sizeof( pointcloud_vert );
  83
  84    glBindBuffer( GL_ARRAY_BUFFER, pointcloud.vbo );
  85    glBufferData( GL_ARRAY_BUFFER, stride * POINTCLOUD_POINTS,
  86                  NULL, GL_DYNAMIC_DRAW );
  87
  88    /* 0: coordinates */
  89    glVertexAttribPointer( 0, 4, GL_SHORT, GL_TRUE, stride, (void*)0 );
  90    glEnableVertexAttribArray( 0 );
  91
  92    /* 1: colour */
  93    glVertexAttribPointer( 1, 4, GL_UNSIGNED_BYTE, GL_TRUE,
  94                      stride, (void *)offsetof(pointcloud_vert, colour) );
  95    glEnableVertexAttribArray( 1 );
  96    VG_CHECK_GL_ERR();
  97 }
  98
  99 static void pointcloud_init(void){
 100    vg_async_call( async_pointcloud_alloc, NULL, 0 );
 101    shader_point_map_register();
 102 }
 103
 104 static void pointcloud_animate( enum pointcloud_anim anim ){
 105    pointcloud.anim = anim;
 106    pointcloud.anim_start = vg.time;
 107 }
 108
 109 static int pointcloud_idle(void){
 110    if( pointcloud.anim >= k_pointcloud_anim_idle_any ) return 1;
 111    else return 0;
 112 }
 113
 114 static
 115 void pointcloud_render( world_instance *world, camera *cam, m4x3f model ){
 116    if( pointcloud.anim < k_pointcloud_anim_idle_any ){
 117       f32 const k_transition = 0.6f;
 118       f32 t = (vg.time - pointcloud.anim_start) / k_transition;
 119
 120       if( pointcloud.anim == k_pointcloud_anim_hiding ){
 121          if( t > 1.0f ){
 122             pointcloud.visibility = 0.0f;
 123             pointcloud.anim = k_pointcloud_anim_idle_closed;
 124          }
 125          else pointcloud.visibility = 1.0f-t;
 126       }
 127       else if( pointcloud.anim == k_pointcloud_anim_opening ){
 128          if( t > 1.0f ){
 129             pointcloud.visibility = 1.0f;
 130             pointcloud.anim = k_pointcloud_anim_idle_open;
 131          }
 132          else pointcloud.visibility = t;
 133       }
 134    }
 135
 136    if( pointcloud.visibility == 0.0f ) return;
 137
 138    m4x4f upvmprev;
 139    m4x3_expand( model, upvmprev );
 140    m4x4_mul( cam->mtx_prev.pv, upvmprev, upvmprev );
 141
 142    shader_point_map_use();
 143    shader_point_map_uPv( cam->mtx.pv );
 144    shader_point_map_uPvmPrev( upvmprev );
 145    shader_point_map_uMdl( model );
 146    shader_point_map_uCamera( cam->pos );
 147    shader_point_map_uAnim( (v4f){ 32, 1.0f-pointcloud.visibility,
 148                                   0.0f, vg.time } );
 149
 150    glBindVertexArray( pointcloud.vao );
 151    glEnable( GL_PROGRAM_POINT_SIZE );
 152    glDrawArrays( GL_POINTS, 0, pointcloud.count );
 153 }
 154
 155 static void pointcloud_packvert( pointcloud_vert *vert, v3f pos, v4f colour ){
 156    for( u32 i=0; i<3; i++ )
 157       vert->pos[i] = (pos[i]-0.5f) * 32767.0f;
 158
 159    for( u32 i=0; i<4; i++ )
 160       vert->colour[i] = colour[i] * 255.0f;
 161 }
 162
 163 #endif /* POINTCLOUD_H */