1
Fork 0
mirror of https://github.com/RGBCube/serenity synced 2025-05-16 13:44:57 +00:00
serenity/Userland/Libraries/LibGfx/AntiAliasingPainter.h
Florian Stellbrink af3174c9ce LibGFX: Transform vertices when drawing antialiased lines
Previously we transformed each rasterized point when drawing a line.
Now we transform the lines' endpoints instead.

That means running two transforms per line instead of transforms for
each pixel. It is not clear that the overhead for the fast path is
still worth it. If we still want to optimize identity and translations,
it is probably better to do that inside AffineTransform.

In addition this will behave nicer if the transform includes scaling.
Previously this would rasterize lines before scaling. Which means
drawing too many points when scaling down, and not drawing enough
points when scaling up.
With the new approach we will automatically rasterize at pixel scale.

This is essentially the same as OpenGL, where vertices are transformed
and rasterization happens in screen space.
2022-04-11 03:16:37 +02:00

47 lines
2.3 KiB
C++

/*
* Copyright (c) 2021, Ali Mohammad Pur <mpfard@serenityos.org>
*
* SPDX-License-Identifier: BSD-2-Clause
*/
#pragma once
#include <LibGfx/Painter.h>
namespace Gfx {
class AntiAliasingPainter {
public:
explicit AntiAliasingPainter(Painter& painter)
: m_underlying_painter(painter)
{
}
void draw_line(FloatPoint const&, FloatPoint const&, Color, float thickness = 1, Painter::LineStyle style = Painter::LineStyle::Solid, Color alternate_color = Color::Transparent);
void draw_aliased_line(FloatPoint const&, FloatPoint const&, Color, float thickness = 1, Painter::LineStyle style = Painter::LineStyle::Solid, Color alternate_color = Color::Transparent);
void fill_path(Path&, Color, Painter::WindingRule rule = Painter::WindingRule::Nonzero);
void stroke_path(Path const&, Color, float thickness);
void draw_quadratic_bezier_curve(FloatPoint const& control_point, FloatPoint const&, FloatPoint const&, Color, float thickness = 1, Painter::LineStyle style = Painter::LineStyle::Solid);
void draw_cubic_bezier_curve(FloatPoint const& control_point_0, FloatPoint const& control_point_1, FloatPoint const&, FloatPoint const&, Color, float thickness = 1, Painter::LineStyle style = Painter::LineStyle::Solid);
void draw_elliptical_arc(FloatPoint const& p1, FloatPoint const& p2, FloatPoint const& center, FloatPoint const& radii, float x_axis_rotation, float theta_1, float theta_delta, Color, float thickness = 1, Painter::LineStyle style = Painter::LineStyle::Solid);
void translate(float dx, float dy) { m_transform.translate(dx, dy); }
void translate(FloatPoint const& delta) { m_transform.translate(delta); }
void draw_circle(IntPoint center, int radius, Color);
void fill_rect_with_rounded_corners(IntRect const&, Color, int radius);
void fill_rect_with_rounded_corners(IntRect const&, Color, int top_left_radius, int top_right_radius, int bottom_right_radius, int bottom_left_radius);
private:
enum class AntiAliasPolicy {
OnlyEnds,
Full,
};
template<AntiAliasPolicy policy>
void draw_anti_aliased_line(FloatPoint const&, FloatPoint const&, Color, float thickness, Painter::LineStyle style, Color alternate_color);
Painter& m_underlying_painter;
AffineTransform m_transform;
};
}