Function g3_DrawRotatedBitmap

renderer/HardwareDraw.cpp:299–351

Draws a bitmap that has been rotated about its center. Angle of rotation is passed as 'rot_angle'

// Draws a bitmap that has been rotated about its center.  Angle of rotation is passed as 'rot_angle'
void g3_DrawRotatedBitmap(vector *pos, angle rot_angle, float width, float height, int bm, int color) {
  // get the view orientation
  matrix viewOrient;
  g3_GetUnscaledMatrix(&viewOrient);

  matrix rot_matrix;
  vm_AnglesToMatrix(&rot_matrix, 0, 0, rot_angle);

  float w = width;
  float h = height;

  vector rot_vectors[4];
  rot_vectors[0].x = -w;
  rot_vectors[0].y = h;

  rot_vectors[1].x = w;
  rot_vectors[1].y = h;

  rot_vectors[2].x = w;
  rot_vectors[2].y = -h;

  rot_vectors[3].x = -w;
  rot_vectors[3].y = -h;

  g3Point rot_points[8], *pntlist[8];
  int i;
  for (i = 0; i < 4; ++i) {
    vector offset;
    rot_vectors[i].z = 0.0f;
    vm_MatrixMulVector(&offset, &rot_vectors[i], &rot_matrix);

    vector cornerPos = *pos + (viewOrient.uvec * offset.y) + (viewOrient.rvec * offset.x);
    rot_points[i].p3_codes = 0;
    g3_RotatePoint(&rot_points[i], &cornerPos);

    rot_points[i].p3_flags |= PF_UV | PF_RGBA;
    rot_points[i].p3_l = 1.0f;
    rot_points[i].p3_uvl.u = ((i & 1) ^ ((i & 2) >> 1)) ? 1.0f : 0.0f;
    rot_points[i].p3_uvl.v = (i & 2) ? 1.0f : 0.0f;

    pntlist[i] = &rot_points[i];
  }

  // And draw!!
  rend_SetTextureType(TT_LINEAR);

  if (color != -1) {
    rend_SetLighting(LS_FLAT_GOURAUD);
    rend_SetFlatColor(color);
  }

  g3_DrawPoly(4, pntlist, bm);
}

// Draws a bitmap on a specific plane.  Also does rotation.  Angle of rotation is passed as 'rot_angle'
void g3_DrawPlanarRotatedBitmap(vector *pos, vector *norm, angle rot_angle, float width, float height, int bm) {