src/vg/vg_lines.h

   1 /* Copyright (C) 2021-2022 Harry Godden (hgn) - All Rights Reserved */
   2
   3 #ifndef VG_LINES_H
   4 #define VG_LINES_H
   5
   6 #include "vg/vg.h"
   7
   8 static int debug_lines_enable = 0;
   9
  10 #ifdef VG_3D
  11  typedef v3f line_co;
  12 #else
  13  typedef v2f line_co;
  14 #endif
  15
  16 static struct vg_shader _shader_lines =
  17 {
  18    .name = "[vg] lines",
  19    .link = NULL,
  20    .vs =
  21    {
  22       .orig_file = NULL,
  23       .static_src =
  24
  25 #ifdef VG_3D
  26         "uniform mat4 uPv;"
  27         "layout (location=0) in vec3 a_co;"
  28 #else
  29         "uniform mat3 uPv;"
  30         "layout (location=0) in vec2 a_co;"
  31 #endif
  32         "layout (location=1) in vec4 a_colour;"
  33         ""
  34         "out vec4 s_colour;"
  35         ""
  36         "void main()"
  37         "{"
  38 #ifdef VG_3D
  39         "       vec4 vert_pos = uPv * vec4( a_co, 1.0 );"
  40 #else
  41         "       vec4 vert_pos = vec4( uPv * vec3( a_co, 1.0 ), 1.0 );"
  42 #endif
  43         "  s_colour = a_colour;"
  44         "       gl_Position = vert_pos;"
  45         "}"
  46    },
  47    .fs =
  48    {
  49       .orig_file = NULL,
  50       .static_src =
  51
  52         "out vec4 FragColor;"
  53         ""
  54         "in vec4 s_colour;"
  55         ""
  56         "void main()"
  57         "{"
  58         "       FragColor = s_colour;"
  59         "}"
  60    }
  61 };
  62
  63 struct
  64 {
  65         struct vg_lines_vert
  66         {
  67 #ifdef VG_3D
  68       v3f co;
  69 #else
  70                 v2f co;
  71 #endif
  72
  73                 u32 colour;
  74         }
  75         *buffer;
  76
  77         GLuint vao, vbo;
  78         u32 draw_idx, cap, buffer_size;
  79 }
  80 vg_lines;
  81
  82 static void vg_lines_init(void)
  83 {
  84    vg_info( "vg_lines_init\n" );
  85
  86    vg_convar_push( (struct vg_convar){
  87       .name = "debug_lines",
  88       .data = &debug_lines_enable,
  89       .data_type = k_convar_dtype_i32,
  90       .opt_i32 = { .min=0, .max=1, .clamp=1 },
  91       .persistent = 1
  92    });
  93
  94    vg_shader_register( &_shader_lines );
  95
  96    vg_acquire_thread_sync();
  97    {
  98       glGenVertexArrays( 1, &vg_lines.vao );
  99       glGenBuffers( 1, &vg_lines.vbo );
 100       glBindVertexArray( vg_lines.vao );
 101       glBindBuffer( GL_ARRAY_BUFFER, vg_lines.vbo );
 102
 103       vg_lines.cap = 50000;
 104       vg_lines.buffer_size = vg_lines.cap * sizeof( struct vg_lines_vert );
 105
 106       glBufferData( GL_ARRAY_BUFFER, vg_lines.buffer_size,
 107                     NULL, GL_DYNAMIC_DRAW );
 108       glBindVertexArray( vg_lines.vao );
 109       VG_CHECK_GL_ERR();
 110
 111       /* Pointers */
 112       glVertexAttribPointer(
 113          0,
 114          sizeof( vg_lines.buffer[0].co ) / sizeof(float),
 115          GL_FLOAT,
 116          GL_FALSE,
 117          sizeof( struct vg_lines_vert ),
 118          (void *)0
 119       );
 120       glEnableVertexAttribArray( 0 );
 121
 122       glVertexAttribPointer(
 123          1,
 124          4,
 125          GL_UNSIGNED_BYTE,
 126          GL_TRUE,
 127          sizeof( struct vg_lines_vert ),
 128          (void*)(offsetof( struct vg_lines_vert, colour ))
 129       );
 130       glEnableVertexAttribArray( 1 );
 131
 132       VG_CHECK_GL_ERR();
 133
 134       /* Alloc RAM */
 135       vg_lines.buffer = vg_alloc( vg_lines.buffer_size );
 136       vg_success( "done\n" );
 137    }
 138
 139    vg_release_thread_sync();
 140 }
 141
 142 static void vg_lines_free(void *nothing)
 143 {
 144         glDeleteVertexArrays( 1, &vg_lines.vao );
 145         glDeleteBuffers( 1, &vg_lines.vbo );
 146         vg_free( vg_lines.buffer );
 147 }
 148
 149 static void vg_lines_drawall( float* projection )
 150 {
 151         glUseProgram( _shader_lines.id );
 152
 153 #ifdef VG_3D
 154    glUniformMatrix4fv
 155 #else
 156         glUniformMatrix3fv
 157 #endif
 158    ( glGetUniformLocation( _shader_lines.id, "uPv" ), 1, GL_FALSE, projection );
 159
 160         glBindVertexArray( vg_lines.vao );
 161         glBindBuffer( GL_ARRAY_BUFFER, vg_lines.vbo );
 162
 163         glBufferSubData( GL_ARRAY_BUFFER, 0, vg_lines.draw_idx *
 164          sizeof(struct vg_lines_vert), vg_lines.buffer );
 165
 166         glEnable( GL_BLEND );
 167         glBlendFunc( GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA );
 168         glBlendEquation( GL_FUNC_ADD );
 169
 170    if( debug_lines_enable )
 171       glDrawArrays( GL_LINES, 0, vg_lines.draw_idx );
 172
 173         glDisable( GL_BLEND );
 174         vg_lines.draw_idx = 0;
 175 }
 176
 177 static void vg_line2( line_co from, line_co to, u32 fc, u32 tc )
 178 {
 179         struct vg_lines_vert *v = &vg_lines.buffer[vg_lines.draw_idx];
 180
 181 #ifdef VG_3D
 182         v3_copy( from, v[0].co );
 183         v3_copy( to, v[1].co );
 184 #else
 185         v2_copy( from, v[0].co );
 186         v2_copy( to, v[1].co );
 187 #endif
 188
 189         v[0].colour = fc;
 190         v[1].colour = tc;
 191
 192         vg_lines.draw_idx += 2;
 193 }
 194
 195 static void vg_line( line_co from, line_co to, u32 colour )
 196 {
 197         vg_line2( from, to, colour, colour );
 198 }
 199
 200 static void vg_line_box( line_co min, line_co max, u32 colour )
 201 {
 202 #ifdef VG_3D
 203    /* TODO... */
 204 #else
 205         vg_line( min, (v2f){min[0],max[1]}, colour );
 206         vg_line( (v2f){min[0],max[1]}, max, colour );
 207         vg_line( max, (v2f){max[0],min[1]}, colour );
 208         vg_line( (v2f){max[0],min[1]}, min, colour );
 209 #endif
 210 }
 211
 212 static void vg_line_boxf( boxf box, u32 colour )
 213 {
 214    v3f p000, p001, p010, p011, p100, p101, p110, p111;
 215
 216    p000[0]=box[0][0];p000[1]=box[0][1];p000[2]=box[0][2];
 217    p001[0]=box[0][0];p001[1]=box[0][1];p001[2]=box[1][2];
 218    p010[0]=box[0][0];p010[1]=box[1][1];p010[2]=box[0][2];
 219    p011[0]=box[0][0];p011[1]=box[1][1];p011[2]=box[1][2];
 220
 221    p100[0]=box[1][0];p100[1]=box[0][1];p100[2]=box[0][2];
 222    p101[0]=box[1][0];p101[1]=box[0][1];p101[2]=box[1][2];
 223    p110[0]=box[1][0];p110[1]=box[1][1];p110[2]=box[0][2];
 224    p111[0]=box[1][0];p111[1]=box[1][1];p111[2]=box[1][2];
 225
 226    vg_line( p000, p001, colour );
 227    vg_line( p001, p011, colour );
 228    vg_line( p011, p010, colour );
 229    vg_line( p010, p000, colour );
 230
 231    vg_line( p100, p101, colour );
 232    vg_line( p101, p111, colour );
 233    vg_line( p111, p110, colour );
 234    vg_line( p110, p100, colour );
 235
 236    vg_line( p100, p000, colour );
 237    vg_line( p101, p001, colour );
 238    vg_line( p110, p010, colour );
 239    vg_line( p111, p011, colour );
 240 }
 241
 242 static void vg_line_boxf_transformed( m4x3f m, boxf box, u32 colour )
 243 {
 244    v3f p000, p001, p010, p011, p100, p101, p110, p111;
 245
 246    p000[0]=box[0][0];p000[1]=box[0][1];p000[2]=box[0][2];
 247    p001[0]=box[0][0];p001[1]=box[0][1];p001[2]=box[1][2];
 248    p010[0]=box[0][0];p010[1]=box[1][1];p010[2]=box[0][2];
 249    p011[0]=box[0][0];p011[1]=box[1][1];p011[2]=box[1][2];
 250
 251    p100[0]=box[1][0];p100[1]=box[0][1];p100[2]=box[0][2];
 252    p101[0]=box[1][0];p101[1]=box[0][1];p101[2]=box[1][2];
 253    p110[0]=box[1][0];p110[1]=box[1][1];p110[2]=box[0][2];
 254    p111[0]=box[1][0];p111[1]=box[1][1];p111[2]=box[1][2];
 255
 256    m4x3_mulv( m, p000, p000 );
 257    m4x3_mulv( m, p001, p001 );
 258    m4x3_mulv( m, p010, p010 );
 259    m4x3_mulv( m, p011, p011 );
 260    m4x3_mulv( m, p100, p100 );
 261    m4x3_mulv( m, p101, p101 );
 262    m4x3_mulv( m, p110, p110 );
 263    m4x3_mulv( m, p111, p111 );
 264
 265    vg_line( p000, p001, colour );
 266    vg_line( p001, p011, colour );
 267    vg_line( p011, p010, colour );
 268    vg_line( p010, p000, colour );
 269
 270    vg_line( p100, p101, colour );
 271    vg_line( p101, p111, colour );
 272    vg_line( p111, p110, colour );
 273    vg_line( p110, p100, colour );
 274
 275    vg_line( p100, p000, colour );
 276    vg_line( p101, p001, colour );
 277    vg_line( p110, p010, colour );
 278    vg_line( p111, p011, colour );
 279
 280    vg_line( p000, p110, colour );
 281    vg_line( p100, p010, colour );
 282 }
 283
 284 static void vg_line_cross(v3f pos,u32 colour, float scale)
 285 {
 286    v3f p0, p1;
 287    v3_add( (v3f){ scale,0.0f,0.0f}, pos, p0 );
 288    v3_add( (v3f){-scale,0.0f,0.0f}, pos, p1 );
 289    vg_line( p0, p1, colour );
 290    v3_add( (v3f){0.0f, scale,0.0f}, pos, p0 );
 291    v3_add( (v3f){0.0f,-scale,0.0f}, pos, p1 );
 292    vg_line( p0, p1, colour );
 293    v3_add( (v3f){0.0f,0.0f, scale}, pos, p0 );
 294    v3_add( (v3f){0.0f,0.0f,-scale}, pos, p1 );
 295    vg_line( p0, p1, colour );
 296 }
 297
 298 static void vg_line_pt3( v3f pt, float size, u32 colour )
 299 {
 300    boxf box =
 301    {
 302       { pt[0]-size, pt[1]-size, pt[2]-size },
 303       { pt[0]+size, pt[1]+size, pt[2]+size }
 304    };
 305
 306    vg_line_boxf( box, colour );
 307 }
 308
 309 #endif /* VG_LINES_H */