void World::set_tera_height(Plasma &plasma)
{
memset(corner_matrix, 0, sizeof(Corner)*(max_x_loc+1)*(max_y_loc+1));
// short seaHeight = TerrainRes::max_height(TERRAIN_OCEAN);
short seaHeight = 0; // no more sea
int y;
int x;
for(y = 0; y <= max_y_loc; ++y )
{
for(x = 0; x <= max_x_loc; ++x)
{
Corner *cornerPtr = get_corner(x,y);
cornerPtr->set_altitude(plasma.get_pix(x,y));
cornerPtr->set_sea_altitude(seaHeight);
// set gradient_x
float gradientX;
if(x <= 0)
{
err_when(x < 0);
gradientX = float(4*plasma.get_pix(x+1,y) - plasma.get_pix(x+2,y) - 3*plasma.get_pix(x,y))
/ (2 * LOCATE_WIDTH);
}
else if( x >= max_x_loc )
{
err_when(x > max_x_loc);
gradientX = float(plasma.get_pix(x-2,y) - 4*plasma.get_pix(x-1,y) + 3*plasma.get_pix(x,y))
/ (2 * LOCATE_WIDTH);
}
else
{
gradientX = float(plasma.get_pix(x+1,y) - plasma.get_pix(x-1,y))
/ (2 * LOCATE_WIDTH);
}
// if( gradientX >= 0.0f && gradientX <= 0.25f )
// gradientX += 0.15f;
// else if( gradientX < 0.0f && gradientX >= -0.25f )
// gradientX -= 0.15f;
cornerPtr->set_gradient_x( gradientX );
// set gradient_y
float gradientY;
if(y <= 0)
{
err_when(y < 0);
gradientY = float(4*plasma.get_pix(x,y+1) - plasma.get_pix(x,y+2) - 3*plasma.get_pix(x,y))
/ (2 * LOCATE_HEIGHT);
}
else if( y >= max_y_loc )
{
err_when(y > max_y_loc);
gradientY = float(plasma.get_pix(x,y-2) - 4*plasma.get_pix(x,y-1) + 3*plasma.get_pix(x,y))
/ (2 * LOCATE_HEIGHT);
}
else
{
gradientY = float(plasma.get_pix(x,y+1) - plasma.get_pix(x,y-1))
/ (2 * LOCATE_HEIGHT);
}
// if( gradientY >= 0.0f && gradientY <= 0.25f )
// gradientY += 0.15f;
// else if( gradientY < 0.0f && gradientY >= -0.25f )
// gradientY -= 0.15f;
cornerPtr->set_gradient_y( gradientY );
}
}
// calculate polynomial coefficient
for(y = 0; y < max_y_loc; ++y )
{
for(x = 0; x < max_x_loc; ++x)
{
LocationCorners lc;
get_loc_corner(x,y, &lc);
short &z0 = lc.top_left->altitude;
short &z1 = lc.top_right->altitude;
short &z2 = lc.bottom_left->altitude;
short &z3 = lc.bottom_right->altitude;
short &duz0w = lc.top_left->gradient_x; // du/dz * LOCATE_WIDTH
short &dvz0h = lc.top_left->gradient_y;
short &duz1w = lc.top_right->gradient_x;
short &dvz1h = lc.top_right->gradient_y;
short &duz2w = lc.bottom_left->gradient_x;
short &dvz2h = lc.bottom_left->gradient_y;
short &duz3w = lc.bottom_right->gradient_x;
short &dvz3h = lc.bottom_right->gradient_y;
lc.loc_ptr->c30 = (duz1w + duz0w - (z1-z0) * 2) << (C_MULTIPLIER_SHIFT - LOCATE_WIDTH_SHIFT - LOCATE_WIDTH_SHIFT - LOCATE_WIDTH_SHIFT);
lc.loc_ptr->c21 = (duz3w + duz0w - duz1w - duz2w) << (C_MULTIPLIER_SHIFT - 1 - LOCATE_WIDTH_SHIFT - LOCATE_WIDTH_SHIFT - LOCATE_HEIGHT_SHIFT);
lc.loc_ptr->c12 = (dvz3h + dvz0h - dvz1h - dvz2h) << (C_MULTIPLIER_SHIFT - 1 - LOCATE_WIDTH_SHIFT - LOCATE_HEIGHT_SHIFT - LOCATE_HEIGHT_SHIFT);
lc.loc_ptr->c03 = (dvz2h + dvz0h - (z2-z0) * 2) << (C_MULTIPLIER_SHIFT - LOCATE_HEIGHT_SHIFT - LOCATE_HEIGHT_SHIFT - LOCATE_HEIGHT_SHIFT);
lc.loc_ptr->c20 = ( (z1-z0) * 3 - duz1w - duz0w * 2 ) << (C_MULTIPLIER_SHIFT - LOCATE_WIDTH_SHIFT - LOCATE_WIDTH_SHIFT);
lc.loc_ptr->c11 = (( z3 + z0 - z1 - z2 ) << (C_MULTIPLIER_SHIFT - LOCATE_WIDTH_SHIFT - LOCATE_HEIGHT_SHIFT))
- (lc.loc_ptr->c21 << LOCATE_WIDTH_SHIFT) - (lc.loc_ptr->c12 << LOCATE_HEIGHT_SHIFT);
lc.loc_ptr->c02 = ( (z2-z0) * 3 - dvz2h - dvz0h * 2 ) << (C_MULTIPLIER_SHIFT - LOCATE_HEIGHT_SHIFT - LOCATE_HEIGHT_SHIFT);
lc.loc_ptr->c00 = z0 << C_MULTIPLIER_SHIFT;
lc.loc_ptr->c10 = duz0w << (C_MULTIPLIER_SHIFT - LOCATE_WIDTH_SHIFT);
lc.loc_ptr->c01 = dvz0h << (C_MULTIPLIER_SHIFT - LOCATE_HEIGHT_SHIFT);
// find the height of the rendered bitmap
{
lc.loc_ptr->min_y = 0;
lc.loc_ptr->max_y = 0;
int seaLevel = 0;
if( lc.top_left->is_sea() )
seaLevel = lc.top_left->sea_altitude;
if( lc.top_right->is_sea() )
seaLevel = lc.top_right->sea_altitude;
if( lc.bottom_left->is_sea() )
seaLevel = lc.bottom_left->sea_altitude;
if( lc.bottom_right->is_sea() )
seaLevel = lc.bottom_right->sea_altitude;
if( seaLevel )
lc.loc_ptr->loc_flag |= LOCATE_SEA_COAST;
else
lc.loc_ptr->loc_flag &= ~LOCATE_SEA_COAST;
// height relative to top left corner
// int refHeight = ZoomMatrix::calc_abs_y(0, 0, lc.loc_ptr->evaluate_z(0, 0));
int refHeight = ZoomMatrix::calc_abs_y(0, 0, lc.loc_ptr->c00 >> C_MULTIPLIER_SHIFT);
// include LOCATE_WIDTH, LOCATE_HEIGHT for wider min_y, max_y
for(int v = 0; v <= LOCATE_HEIGHT; v+=LOCATE_HEIGHT/4 )
{
for( int u = 0; u <= LOCATE_WIDTH; u+=LOCATE_WIDTH/4 )
{
long z = lc.loc_ptr->evaluate_z(u, v);
// if cover by sea
if( seaLevel && z < seaLevel )
z = seaLevel;
int pointY = ZoomMatrix::calc_abs_y(u, v, z) - refHeight;
//(z - z0) * ZOOM_Z_HEIGHT
//+ (u * ZOOM_LOC_X_HEIGHT * LOCATE_HEIGHT
//+ v * ZOOM_LOC_Y_HEIGHT * LOCATE_WIDTH )
//>> (LOCATE_WIDTH_SHIFT + LOCATE_HEIGHT_SHIFT);
if( pointY < lc.loc_ptr->min_y)
lc.loc_ptr->min_y = pointY;
if( pointY > lc.loc_ptr->max_y)
lc.loc_ptr->max_y = pointY;
}
}
lc.loc_ptr->min_y -= 8; // -4 for more space
lc.loc_ptr->max_y += 8; // +4 for more space
}
}
}
}
