render.h

   1 #ifndef RENDER_H
   2 #define RENDER_H
   3
   4 #include "common.h"
   5 #include "model.h"
   6
   7 static struct pipeline
   8 {
   9    float fov;
  10    glmesh fsquad;
  11
  12    GLuint fb_background,
  13           rgb_background;
  14 }
  15 gpipeline;
  16
  17 static void render_water_texture( m4x3f camera );
  18 static void render_water_surface( m4x4f pv );
  19 static void render_world( m4x4f projection, m4x3f camera );
  20
  21 /*
  22  * http://www.terathon.com/lengyel/Lengyel-Oblique.pdf
  23  */
  24 static void plane_clip_projection( m4x4f mat, v4f plane )
  25 {
  26    v4f c =
  27    {
  28       (vg_signf(plane[0]) + mat[2][0]) / mat[0][0],
  29       (vg_signf(plane[1]) + mat[2][1]) / mat[1][1],
  30       -1.0f,
  31       (1.0f + mat[2][2]) / mat[3][2]
  32    };
  33
  34    v4_muls( plane, 2.0f / v4_dot(plane,c), c );
  35
  36    mat[0][2] = c[0];
  37    mat[1][2] = c[1];
  38    mat[2][2] = c[2] + 1.0f;
  39    mat[3][2] = c[3];
  40 }
  41
  42 static void pipeline_projection( m4x4f mat, float nearz, float farz )
  43 {
  44    m4x4_projection( mat,
  45          gpipeline.fov,
  46          (float)vg_window_x / (float)vg_window_y,
  47          nearz, farz );
  48 }
  49
  50 static void create_renderbuffer_std( GLuint *fb, GLuint *rgb, GLuint *rb )
  51 {
  52    glGenFramebuffers( 1, fb );
  53    glBindFramebuffer( GL_FRAMEBUFFER, *fb );
  54
  55    glGenTextures( 1, rgb );
  56    glBindTexture( GL_TEXTURE_2D, *rgb );
  57    glTexImage2D( GL_TEXTURE_2D, 0, GL_RGB, vg_window_x, vg_window_y,
  58          0, GL_RGB, GL_UNSIGNED_BYTE, NULL);
  59
  60    glTexParameteri( GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR );
  61    glTexParameteri( GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR );
  62    glFramebufferTexture2D( GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0,
  63          GL_TEXTURE_2D, *rgb, 0);
  64
  65    /* TODO: Check for DEPTH32f availiblity and use if possible */
  66
  67    glGenRenderbuffers( 1, rb );
  68    glBindRenderbuffer( GL_RENDERBUFFER, *rb );
  69    glRenderbufferStorage( GL_RENDERBUFFER, GL_DEPTH24_STENCIL8,
  70          vg_window_x, vg_window_y );
  71
  72    glFramebufferRenderbuffer( GL_FRAMEBUFFER, GL_DEPTH_STENCIL_ATTACHMENT,
  73          GL_RENDERBUFFER, *rb );
  74 }
  75
  76 static void resize_renderbuffer_std( GLuint *fb, GLuint *rgb, GLuint *rb )
  77 {
  78    glBindTexture( GL_TEXTURE_2D, *rgb );
  79    glTexImage2D( GL_TEXTURE_2D, 0, GL_RGB, vg_window_x, vg_window_y, 0,
  80          GL_RGB, GL_UNSIGNED_BYTE, NULL );
  81
  82    glBindRenderbuffer( GL_RENDERBUFFER, *rb );
  83    glRenderbufferStorage( GL_RENDERBUFFER, GL_DEPTH24_STENCIL8,
  84          vg_window_x, vg_window_y );
  85 }
  86
  87 static void render_fb_resize(void)
  88 {
  89    glBindTexture( GL_TEXTURE_2D, gpipeline.rgb_background );
  90    glTexImage2D( GL_TEXTURE_2D, 0, GL_RGB, vg_window_x, vg_window_y, 0,
  91          GL_RGB, GL_UNSIGNED_BYTE, NULL );
  92 }
  93
  94 static void render_init(void)
  95 {
  96    glGenFramebuffers( 1, &gpipeline.fb_background );
  97    glBindFramebuffer( GL_FRAMEBUFFER, gpipeline.fb_background );
  98
  99    glGenTextures( 1, &gpipeline.rgb_background );
 100    glBindTexture( GL_TEXTURE_2D, gpipeline.rgb_background );
 101    glTexImage2D( GL_TEXTURE_2D, 0, GL_RGB, vg_window_x, vg_window_y,
 102          0, GL_RGB, GL_UNSIGNED_BYTE, NULL);
 103
 104    glTexParameteri( GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR );
 105    glTexParameteri( GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR );
 106    glFramebufferTexture2D( GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0,
 107          GL_TEXTURE_2D,
 108          gpipeline.rgb_background, 0);
 109
 110    float quad[] = { 0.0f, 0.0f, 1.0f, 1.0f, 0.0f, 1.0f,
 111                     0.0f, 0.0f, 1.0f, 0.0f, 1.0f, 1.0f };
 112
 113    glGenVertexArrays( 1, &gpipeline.fsquad.vao );
 114    glGenBuffers( 1, &gpipeline.fsquad.vbo );
 115    glBindVertexArray( gpipeline.fsquad.vao );
 116    glBindBuffer( GL_ARRAY_BUFFER, gpipeline.fsquad.vbo );
 117    glBufferData( GL_ARRAY_BUFFER, sizeof(quad), quad, GL_STATIC_DRAW );
 118    glBindVertexArray( gpipeline.fsquad.vao );
 119    glVertexAttribPointer( 0, 2, GL_FLOAT, GL_FALSE,
 120          sizeof(float)*2, (void*)0 );
 121    glEnableVertexAttribArray( 0 );
 122    VG_CHECK_GL();
 123 }
 124
 125 static void render_fsquad(void)
 126 {
 127    glBindVertexArray( gpipeline.fsquad.vao );
 128    glDrawArrays( GL_TRIANGLES, 0, 6 );
 129 }
 130
 131 #endif /* RENDER_H */