godot/scene/2d/line_builder.h

/*************************************************************************/
/*  line_builder.h                                                       */
/*************************************************************************/
/*                       This file is part of:                           */
/*                           GODOT ENGINE                                */
/*                      https://godotengine.org                          */
/*************************************************************************/
/* Copyright (c) 2007-2019 Juan Linietsky, Ariel Manzur.                 */
/* Copyright (c) 2014-2019 Godot Engine contributors (cf. AUTHORS.md)    */
/*                                                                       */
/* Permission is hereby granted, free of charge, to any person obtaining */
/* a copy of this software and associated documentation files (the       */
/* "Software"), to deal in the Software without restriction, including   */
/* without limitation the rights to use, copy, modify, merge, publish,   */
/* distribute, sublicense, and/or sell copies of the Software, and to    */
/* permit persons to whom the Software is furnished to do so, subject to */
/* the following conditions:                                             */
/*                                                                       */
/* The above copyright notice and this permission notice shall be        */
/* included in all copies or substantial portions of the Software.       */
/*                                                                       */
/* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,       */
/* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF    */
/* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.*/
/* IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY  */
/* CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,  */
/* TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE     */
/* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.                */
/*************************************************************************/

#ifndef LINE_BUILDER_H
#define LINE_BUILDER_H

#include "core/color.h"
#include "core/math/vector2.h"
#include "line_2d.h"
#include "scene/resources/color_ramp.h"

class LineBuilder {
public:
	// TODO Move in a struct and reference it
	// Input
	Vector<Vector2> points;
	Line2D::LineJointMode joint_mode;
	Line2D::LineCapMode begin_cap_mode;
	Line2D::LineCapMode end_cap_mode;
	float width;
	Color default_color;
	Gradient *gradient;
	Line2D::LineTextureMode texture_mode;
	float sharp_limit;
	int round_precision;
	float tile_aspect; // w/h
	// TODO offset_joints option (offers alternative implementation of round joints)

	// TODO Move in a struct and reference it
	// Output
	Vector<Vector2> vertices;
	Vector<Color> colors;
	Vector<Vector2> uvs;
	Vector<int> indices;

	LineBuilder();

	void build();
	void clear_output();

private:
	enum Orientation {
		UP = 0,
		DOWN = 1
	};

	// Triangle-strip methods
	void strip_begin(Vector2 up, Vector2 down, Color color, float uvx);
	void strip_new_quad(Vector2 up, Vector2 down, Color color, float uvx);
	void strip_add_quad(Vector2 up, Vector2 down, Color color, float uvx);
	void strip_add_tri(Vector2 up, Orientation orientation);
	void strip_add_arc(Vector2 center, float angle_delta, Orientation orientation);

	void new_arc(Vector2 center, Vector2 vbegin, float angle_delta, Color color, Rect2 uv_rect);

private:
	bool _interpolate_color;
	int _last_index[2]; // Index of last up and down vertices of the strip
};

#endif // LINE_BUILDER_H