/*************************************************************************/ /* gradient.h */ /*************************************************************************/ /* This file is part of: */ /* GODOT ENGINE */ /* https://godotengine.org */ /*************************************************************************/ /* Copyright (c) 2007-2022 Juan Linietsky, Ariel Manzur. */ /* Copyright (c) 2014-2022 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 GRADIENT_H #define GRADIENT_H #include "core/io/resource.h" class Gradient : public Resource { GDCLASS(Gradient, Resource); OBJ_SAVE_TYPE(Gradient); public: enum InterpolationMode { GRADIENT_INTERPOLATE_LINEAR, GRADIENT_INTERPOLATE_CONSTANT, GRADIENT_INTERPOLATE_CUBIC, }; struct Point { float offset = 0.0; Color color; bool operator<(const Point &p_ponit) const { return offset < p_ponit.offset; } }; private: Vector<Point> points; bool is_sorted = true; InterpolationMode interpolation_mode = GRADIENT_INTERPOLATE_LINEAR; _FORCE_INLINE_ void _update_sorting() { if (!is_sorted) { points.sort(); is_sorted = true; } } protected: static void _bind_methods(); public: Gradient(); virtual ~Gradient(); void add_point(float p_offset, const Color &p_color); void remove_point(int p_index); void set_points(Vector<Point> &p_points); Vector<Point> &get_points(); void reverse(); void set_offset(int pos, const float offset); float get_offset(int pos); void set_color(int pos, const Color &color); Color get_color(int pos); void set_offsets(const Vector<float> &p_offsets); Vector<float> get_offsets() const; void set_colors(const Vector<Color> &p_colors); Vector<Color> get_colors() const; void set_interpolation_mode(InterpolationMode p_interp_mode); InterpolationMode get_interpolation_mode(); _FORCE_INLINE_ float cubic_interpolate(float p0, float p1, float p2, float p3, float x) { return p1 + 0.5 * x * (p2 - p0 + x * (2.0 * p0 - 5.0 * p1 + 4.0 * p2 - p3 + x * (3.0 * (p1 - p2) + p3 - p0))); } _FORCE_INLINE_ Color get_color_at_offset(float p_offset) { if (points.is_empty()) { return Color(0, 0, 0, 1); } _update_sorting(); // Binary search. int low = 0; int high = points.size() - 1; int middle = 0; #ifdef DEBUG_ENABLED if (low > high) { ERR_PRINT("low > high, this may be a bug"); } #endif while (low <= high) { middle = (low + high) / 2; const Point &point = points[middle]; if (point.offset > p_offset) { high = middle - 1; //search low end of array } else if (point.offset < p_offset) { low = middle + 1; //search high end of array } else { return point.color; } } // Return interpolated value. if (points[middle].offset > p_offset) { middle--; } int first = middle; int second = middle + 1; if (second >= points.size()) { return points[points.size() - 1].color; } if (first < 0) { return points[0].color; } const Point &pointFirst = points[first]; const Point &pointSecond = points[second]; switch (interpolation_mode) { case GRADIENT_INTERPOLATE_LINEAR: { return pointFirst.color.lerp(pointSecond.color, (p_offset - pointFirst.offset) / (pointSecond.offset - pointFirst.offset)); } break; case GRADIENT_INTERPOLATE_CONSTANT: { return pointFirst.color; } break; case GRADIENT_INTERPOLATE_CUBIC: { int p0 = first - 1; int p3 = second + 1; if (p3 >= points.size()) { p3 = second; } if (p0 < 0) { p0 = first; } const Point &pointP0 = points[p0]; const Point &pointP3 = points[p3]; float x = (p_offset - pointFirst.offset) / (pointSecond.offset - pointFirst.offset); float r = cubic_interpolate(pointP0.color.r, pointFirst.color.r, pointSecond.color.r, pointP3.color.r, x); float g = cubic_interpolate(pointP0.color.g, pointFirst.color.g, pointSecond.color.g, pointP3.color.g, x); float b = cubic_interpolate(pointP0.color.b, pointFirst.color.b, pointSecond.color.b, pointP3.color.b, x); float a = cubic_interpolate(pointP0.color.a, pointFirst.color.a, pointSecond.color.a, pointP3.color.a, x); return Color(r, g, b, a); } break; default: { // Fallback to linear interpolation. return pointFirst.color.lerp(pointSecond.color, (p_offset - pointFirst.offset) / (pointSecond.offset - pointFirst.offset)); } } } int get_points_count() const; }; VARIANT_ENUM_CAST(Gradient::InterpolationMode); #endif // GRADIENT_H