Function gamma_callback

Descent3/config.cpp:486–553

static void gamma_callback(newuiTiledWindow *wnd, void *data) {
  int bm_handle = *((int *)data);

  g3Point pnts[4], *pntlist[4];
  rend_SetColorModel(CM_RGB);
  rend_SetAlphaType(AT_ALWAYS);
  rend_SetTextureType(TT_LINEAR);
  rend_SetLighting(LS_NONE);
  rend_SetOverlayType(OT_NONE);
  rend_SetWrapType(WT_WRAP);
  rend_SetZBufferState(0);

  // First draw checkboard
  int startx = GAMMA_SLICE_X;

  for (int i = 0; i < 4; i++) {
    pntlist[i] = &pnts[i];
    pnts[i].p3_z = 0;
    pnts[i].p3_r = 1;
    pnts[i].p3_g = 1;
    pnts[i].p3_b = 1;
    pnts[i].p3_flags = PF_PROJECTED;
  }

  pnts[0].p3_sx = startx;
  pnts[0].p3_sy = GAMMA_SLICE_Y;
  pnts[0].p3_u = 0;
  pnts[0].p3_v = 0;

  pnts[1].p3_sx = startx + GAMMA_SLICE_WIDTH;
  pnts[1].p3_sy = GAMMA_SLICE_Y;
  pnts[1].p3_u = 2;
  pnts[1].p3_v = 0;

  pnts[2].p3_sx = startx + GAMMA_SLICE_WIDTH;
  pnts[2].p3_sy = GAMMA_SLICE_Y + GAMMA_SLICE_HEIGHT;
  pnts[2].p3_u = 2;
  pnts[2].p3_v = 1;

  pnts[3].p3_sx = startx;
  pnts[3].p3_sy = GAMMA_SLICE_Y + GAMMA_SLICE_HEIGHT;
  pnts[3].p3_u = 0;
  pnts[3].p3_v = 1;

  rend_DrawPolygon2D(bm_handle, pntlist, 4);

  // Now draw grey in the center
  int int_val = 8;
  rend_SetFlatColor(GR_RGB(int_val, int_val, int_val));
  rend_SetTextureType(TT_FLAT);

  pnts[0].p3_sx += 64;
  pnts[0].p3_sy += 32;

  pnts[1].p3_sx -= 64;
  pnts[1].p3_sy += 32;

  pnts[2].p3_sx -= 64;