Method CargoClickedAt

src/industry_gui.cpp:2282–2333

* Decide which cargo was clicked at in a #CFT_CARGO field. * @param left Left industry neighbour if available (else \c nullptr should be supplied). * @param right Right industry neighbour if available (else \c nullptr should be supplied). * @param pt Click position in the cargo field. * @return Cargo clicked at, or #INVALID_CARGO if none. */

	 * @return Cargo clicked at, or #INVALID_CARGO if none.
	 */
	CargoType CargoClickedAt(const CargoesField *left, const CargoesField *right, Point pt) const
	{
		assert(this->type == CFT_CARGO);

		/* Vertical matching. */
		int cpos = this->GetCargoBase(0);
		uint col;
		for (col = 0; col < this->u.cargo.num_cargoes; col++) {
			if (pt.x < cpos) break;
			if (pt.x < cpos + static_cast<int>(CargoesField::cargo_line.width)) return this->u.cargo.vertical_cargoes[col];
			cpos += CargoesField::cargo_line.width + CargoesField::cargo_space.width;
		}
		/* col = 0 -> left of first col, 1 -> left of 2nd col, ... this->u.cargo.num_cargoes right of last-col. */

		int vpos = (vert_inter_industry_space / 2) + CargoesField::cargo_border.height + (GetCharacterHeight(FS_NORMAL) - CargoesField::cargo_line.height) / 2;
		uint row;
		for (row = 0; row < MAX_CARGOES; row++) {
			if (pt.y < vpos) return INVALID_CARGO;
			if (pt.y < vpos + static_cast<int>(CargoesField::cargo_line.height)) break;
			vpos += GetCharacterHeight(FS_NORMAL) + CargoesField::cargo_space.height;
		}
		if (row == MAX_CARGOES) return INVALID_CARGO;

		/* row = 0 -> at first horizontal row, row = 1 -> second horizontal row, 2 = 3rd horizontal row. */
		if (col == 0) {
			if (HasBit(this->u.cargo.supp_cargoes, row)) return this->u.cargo.vertical_cargoes[row];
			if (left != nullptr) {
				if (left->type == CFT_INDUSTRY) return left->u.industry.other_produced[row];
				if (left->type == CFT_CARGO_LABEL && !left->u.cargo_label.left_align) return left->u.cargo_label.cargoes[row];
			}
			return INVALID_CARGO;
		}
		if (col == this->u.cargo.num_cargoes) {
			if (HasBit(this->u.cargo.cust_cargoes, row)) return this->u.cargo.vertical_cargoes[row];
			if (right != nullptr) {
				if (right->type == CFT_INDUSTRY) return right->u.industry.other_accepted[row];
				if (right->type == CFT_CARGO_LABEL && right->u.cargo_label.left_align) return right->u.cargo_label.cargoes[row];
			}
			return INVALID_CARGO;
		}
		if (row >= col) {
			/* Clicked somewhere in-between vertical cargo connection.
			 * Since the horizontal connection is made in the same order as the vertical list, the above condition
			 * ensures we are left-below the main diagonal, thus at the supplying side.
			 */
			if (HasBit(this->u.cargo.supp_cargoes, row)) return this->u.cargo.vertical_cargoes[row];
			return INVALID_CARGO;
		}
		/* Clicked at a customer connection. */
		if (HasBit(this->u.cargo.cust_cargoes, row)) return this->u.cargo.vertical_cargoes[row];
		return INVALID_CARGO;
	}

	/**
	 * Decide what cargo the user clicked in the cargo label field.