render.h

   1 /*
   2  * Copyright (C) 2021-2022 Mt.ZERO Software, Harry Godden - All Rights Reserved
   3  */
   4
   5 #include "common.h"
   6 #include "model.h"
   7
   8 #include "shaders/blit.h"
   9 #include "shaders/standard.h"
  10 #include "shaders/vblend.h"
  11
  12 VG_STATIC void render_water_texture( m4x3f camera );
  13 VG_STATIC void render_water_surface( m4x4f pv, m4x3f camera );
  14 VG_STATIC void render_world( m4x4f projection, m4x3f camera );
  15 VG_STATIC void shader_link_standard_ub( GLuint shader, int texture_id );
  16 VG_STATIC void render_world_depth( m4x4f projection, m4x3f camera );
  17
  18 #ifndef RENDER_H
  19 #define RENDER_H
  20
  21 struct framebuffer
  22 {
  23    GLuint fb, colour, rb;
  24    int div;
  25    GLuint format;
  26
  27    int allocated;
  28 };
  29
  30 VG_STATIC struct pipeline
  31 {
  32    float fov;
  33    glmesh fsquad;
  34
  35    GLuint fb_background,
  36           rgb_background;
  37
  38    /* STD140 */
  39    struct ub_world_lighting
  40    {
  41       /* v3f (padded) */
  42       v4f g_light_colours[3],
  43           g_light_directions[3],
  44           g_ambient_colour;
  45
  46       v4f g_water_plane,
  47           g_depth_bounds;
  48
  49       float g_water_fog;
  50       int g_light_count;
  51       int g_light_preview;
  52       int g_shadow_samples;
  53    }
  54    ub_world_lighting;
  55
  56    struct light_widget
  57    {
  58       int enabled;
  59       v2f dir;
  60       v3f colour;
  61    }
  62    widgets[3];
  63
  64    float shadow_spread, shadow_length;
  65
  66    GLuint fb_depthmap, rgb_depthmap;
  67    GLuint ubo_world_lighting,
  68           ubo_world;
  69
  70    int ready;
  71 }
  72 gpipeline =
  73 {
  74    .widgets =
  75    {
  76       {
  77          .enabled = 1,
  78          .colour = { 1.36f, 1.35f, 1.01f },
  79          .dir = { 0.63f, -0.08f }
  80       },
  81       {
  82          .enabled = 1,
  83          .colour = { 0.33f, 0.56f, 0.64f },
  84          .dir = { -2.60f, -0.13f }
  85       },
  86       {
  87          .enabled = 1,
  88          .colour = { 0.05f, 0.05f, 0.23f },
  89          .dir = { 2.60f, -0.84f }
  90       }
  91    },
  92    .shadow_spread = 0.65f,
  93    .shadow_length = 9.50f,
  94
  95    .ub_world_lighting =
  96    {
  97       .g_ambient_colour = { 0.09f, 0.03f, 0.07f }
  98    }
  99 };
 100
 101 /*
 102  * Matrix Projections
 103  */
 104 /*
 105  * http://www.terathon.com/lengyel/Lengyel-Oblique.pdf
 106  */
 107 VG_STATIC void plane_clip_projection( m4x4f mat, v4f plane )
 108 {
 109    v4f c =
 110    {
 111       (vg_signf(plane[0]) + mat[2][0]) / mat[0][0],
 112       (vg_signf(plane[1]) + mat[2][1]) / mat[1][1],
 113       -1.0f,
 114       (1.0f + mat[2][2]) / mat[3][2]
 115    };
 116
 117    v4_muls( plane, 2.0f / v4_dot(plane,c), c );
 118
 119    mat[0][2] = c[0];
 120    mat[1][2] = c[1];
 121    mat[2][2] = c[2] + 1.0f;
 122    mat[3][2] = c[3];
 123 }
 124
 125 VG_STATIC void pipeline_projection( m4x4f mat, float nearz, float farz )
 126 {
 127    m4x4_projection( mat,
 128          gpipeline.fov,
 129          (float)vg.window_x / (float)vg.window_y,
 130          nearz, farz );
 131 }
 132
 133 /*
 134  * Shaders
 135  */
 136 VG_STATIC void shader_link_standard_ub( GLuint shader, int texture_id )
 137 {
 138    GLuint idx = glGetUniformBlockIndex( shader, "ub_world_lighting" );
 139    glUniformBlockBinding( shader, idx, 0 );
 140
 141    glActiveTexture( GL_TEXTURE0 + texture_id );
 142    glBindTexture( GL_TEXTURE_2D, gpipeline.rgb_depthmap );
 143    glUniform1i( glGetUniformLocation( shader, "g_world_depth" ), texture_id );
 144 }
 145
 146 VG_STATIC void render_update_lighting_ub(void)
 147 {
 148    struct ub_world_lighting *winf = &gpipeline.ub_world_lighting;
 149    int c = 0;
 150
 151    for( int i=0; i<3; i++ )
 152    {
 153       struct light_widget *lw = &gpipeline.widgets[i];
 154
 155       if( lw->enabled )
 156       {
 157          float pitch = lw->dir[0],
 158                yaw = lw->dir[1],
 159                xz = cosf( pitch );
 160
 161          v3_copy( (v3f){ xz*cosf(yaw), sinf(pitch), xz*sinf(yaw) },
 162                winf->g_light_directions[c] );
 163          v3_copy( lw->colour, winf->g_light_colours[c] );
 164
 165          c ++;
 166       }
 167    }
 168
 169    winf->g_light_count = c;
 170    winf->g_light_directions[0][3] = gpipeline.shadow_length;
 171    winf->g_light_colours[0][3] = gpipeline.shadow_spread;
 172
 173    if( vg.quality_profile == k_quality_profile_low )
 174       winf->g_shadow_samples = 0;
 175    else
 176       winf->g_shadow_samples = 8;
 177
 178    glBindBuffer( GL_UNIFORM_BUFFER, gpipeline.ubo_world_lighting );
 179    glBufferSubData( GL_UNIFORM_BUFFER, 0, sizeof(struct ub_world_lighting),
 180          &gpipeline.ub_world_lighting );
 181 }
 182
 183 /*
 184  * Framebuffers
 185  */
 186
 187 VG_STATIC void fb_use( struct framebuffer *fb )
 188 {
 189    if( !fb )
 190    {
 191       glBindFramebuffer( GL_FRAMEBUFFER, 0 );
 192       glViewport( 0, 0, vg.window_x, vg.window_y );
 193    }
 194    else
 195    {
 196       glBindFramebuffer( GL_FRAMEBUFFER, fb->fb );
 197       glViewport( 0, 0, vg.window_x / fb->div, vg.window_y / fb->div );
 198    }
 199 }
 200
 201 VG_STATIC void fb_init( struct framebuffer *fb )
 202 {
 203    i32 ix = vg.window_x / fb->div,
 204        iy = vg.window_y / fb->div;
 205
 206    glGenFramebuffers( 1, &fb->fb );
 207    glBindFramebuffer( GL_FRAMEBUFFER, fb->fb );
 208
 209    glGenTextures( 1, &fb->colour );
 210    glBindTexture( GL_TEXTURE_2D, fb->colour );
 211    glTexImage2D( GL_TEXTURE_2D, 0, fb->format, ix, iy,
 212          0, fb->format, GL_UNSIGNED_BYTE, NULL);
 213
 214    glTexParameteri( GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR );
 215    glTexParameteri( GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR );
 216    glFramebufferTexture2D( GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0,
 217          GL_TEXTURE_2D, fb->colour, 0);
 218
 219    glGenRenderbuffers( 1, &fb->rb );
 220    glBindRenderbuffer( GL_RENDERBUFFER, fb->rb );
 221    glRenderbufferStorage( GL_RENDERBUFFER, GL_DEPTH24_STENCIL8, ix, iy );
 222
 223    glFramebufferRenderbuffer( GL_FRAMEBUFFER, GL_DEPTH_STENCIL_ATTACHMENT,
 224          GL_RENDERBUFFER, fb->rb );
 225    glBindFramebuffer( GL_FRAMEBUFFER, 0 );
 226
 227    VG_CHECK_GL_ERR();
 228    fb->allocated = 1;
 229 }
 230
 231 VG_STATIC void fb_free( struct framebuffer *fb )
 232 {
 233    glDeleteTextures( 1, &fb->colour );
 234    glDeleteFramebuffers( 1, &fb->fb );
 235 }
 236
 237 VG_STATIC void fb_bindtex( struct framebuffer *fb, int texture )
 238 {
 239    glActiveTexture( GL_TEXTURE0 + texture );
 240    glBindTexture( GL_TEXTURE_2D, fb->colour );
 241 }
 242
 243 VG_STATIC void fb_resize( struct framebuffer *fb )
 244 {
 245    if( !fb->allocated )
 246       return;
 247
 248    i32 ix = vg.window_x / fb->div,
 249        iy = vg.window_y / fb->div;
 250
 251    glBindTexture( GL_TEXTURE_2D, fb->colour );
 252    glTexImage2D( GL_TEXTURE_2D, 0, fb->format, ix, iy, 0,
 253          fb->format, GL_UNSIGNED_BYTE, NULL );
 254
 255    glBindRenderbuffer( GL_RENDERBUFFER, fb->rb );
 256    glRenderbufferStorage( GL_RENDERBUFFER, GL_DEPTH24_STENCIL8, ix, iy );
 257 }
 258
 259 VG_STATIC void render_fb_resize(void)
 260 {
 261    if( gpipeline.ready )
 262    {
 263       glBindTexture( GL_TEXTURE_2D, gpipeline.rgb_background );
 264       glTexImage2D( GL_TEXTURE_2D, 0, GL_RGB, vg.window_x, vg.window_y, 0,
 265             GL_RGB, GL_UNSIGNED_BYTE, NULL );
 266    }
 267 }
 268
 269 /* used for drawing player onto */
 270 VG_STATIC void render_init_temp_buffer(void)
 271 {
 272    vg_info( "[render] Allocate temporary framebuffer\n" );
 273
 274    glGenFramebuffers( 1, &gpipeline.fb_background );
 275    glBindFramebuffer( GL_FRAMEBUFFER, gpipeline.fb_background );
 276
 277    glGenTextures( 1, &gpipeline.rgb_background );
 278    glBindTexture( GL_TEXTURE_2D, gpipeline.rgb_background );
 279    glTexImage2D( GL_TEXTURE_2D, 0, GL_RGB, vg.window_x, vg.window_y,
 280          0, GL_RGB, GL_UNSIGNED_BYTE, NULL);
 281
 282    glTexParameteri( GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR );
 283    glTexParameteri( GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR );
 284    glFramebufferTexture2D( GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0,
 285          GL_TEXTURE_2D,
 286          gpipeline.rgb_background, 0);
 287
 288    VG_CHECK_GL_ERR();
 289 }
 290
 291 /* used for drawing world depth from the top view, used in our water and
 292  * lighting calculations */
 293 VG_STATIC void render_init_depthmap_buffer(void)
 294 {
 295    vg_info( "[render] Allocate depth map buffer\n" );
 296
 297    glGenFramebuffers( 1, &gpipeline.fb_depthmap );
 298    glBindFramebuffer( GL_FRAMEBUFFER, gpipeline.fb_depthmap );
 299
 300    glGenTextures( 1, &gpipeline.rgb_depthmap );
 301    glBindTexture( GL_TEXTURE_2D, gpipeline.rgb_depthmap );
 302    glTexImage2D( GL_TEXTURE_2D, 0, GL_R32F, 1024, 1024, 0,
 303          GL_RED, GL_FLOAT, NULL );
 304    glTexParameteri( GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR );
 305    glTexParameteri( GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR );
 306    vg_tex2d_clamp();
 307
 308    glFramebufferTexture2D( GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0,
 309          GL_TEXTURE_2D,
 310          gpipeline.rgb_depthmap, 0);
 311
 312    VG_CHECK_GL_ERR();
 313 }
 314
 315 VG_STATIC void render_init_fs_quad(void)
 316 {
 317    vg_info( "[render] Allocate quad\n" );
 318
 319    float quad[] = { 0.0f, 0.0f, 1.0f, 1.0f, 0.0f, 1.0f,
 320                     0.0f, 0.0f, 1.0f, 0.0f, 1.0f, 1.0f };
 321
 322    glGenVertexArrays( 1, &gpipeline.fsquad.vao );
 323    glGenBuffers( 1, &gpipeline.fsquad.vbo );
 324    glBindVertexArray( gpipeline.fsquad.vao );
 325    glBindBuffer( GL_ARRAY_BUFFER, gpipeline.fsquad.vbo );
 326    glBufferData( GL_ARRAY_BUFFER, sizeof(quad), quad, GL_STATIC_DRAW );
 327    glBindVertexArray( gpipeline.fsquad.vao );
 328    glVertexAttribPointer( 0, 2, GL_FLOAT, GL_FALSE,
 329          sizeof(float)*2, (void*)0 );
 330    glEnableVertexAttribArray( 0 );
 331
 332    VG_CHECK_GL_ERR();
 333 }
 334
 335 VG_STATIC void render_init_uniform_buffers(void)
 336 {
 337    vg_info( "[render] Allocate uniform buffer\n" );
 338
 339    glGenBuffers( 1, &gpipeline.ubo_world_lighting );
 340    glBindBuffer( GL_UNIFORM_BUFFER, gpipeline.ubo_world_lighting );
 341    glBufferData( GL_UNIFORM_BUFFER, sizeof(struct ub_world_lighting),
 342          NULL, GL_DYNAMIC_DRAW );
 343
 344    render_update_lighting_ub();
 345    glBindBufferBase( GL_UNIFORM_BUFFER, 0, gpipeline.ubo_world_lighting );
 346
 347    VG_CHECK_GL_ERR();
 348 }
 349
 350 VG_STATIC void render_init(void)
 351 {
 352    shader_blit_register();
 353    shader_standard_register();
 354    shader_vblend_register();
 355
 356    vg_acquire_thread_sync();
 357    {
 358       render_init_temp_buffer();
 359       render_init_depthmap_buffer();
 360       render_init_fs_quad();
 361       render_init_uniform_buffers();
 362
 363       glBindFramebuffer( GL_FRAMEBUFFER, 0 );
 364       gpipeline.ready = 1;
 365    }
 366
 367    vg_release_thread_sync();
 368 }
 369
 370 /*
 371  * Utility
 372  */
 373 VG_STATIC void render_fsquad(void)
 374 {
 375    glBindVertexArray( gpipeline.fsquad.vao );
 376    glDrawArrays( GL_TRIANGLES, 0, 6 );
 377 }
 378
 379 #endif /* RENDER_H */