genode/repos/demo/include/scout/canvas.h
Norman Feske bb06d879aa os: make 'Genode::Color' C++20 friendly
This patch turns 'Color' from a class to a POD type by replacing
the constructors by the named create functions 'rgb', 'clamped_rgb',
and 'clamped_rgba'. It thereby enables the initialization of Color
values using { .r = ... } syntax and makes the type usable in const
expressions.

It also narrows the type for color components and alpha values to
uint8_t. So possible integer overflows of computed values are detected
by -Wconversion.

As 'Color::rgb(0, 0, 0)' is repeatedly used as a default value, the
patch adds the 'Color::black()' function.

Fixes #5238
2024-06-20 12:54:30 +02:00

193 lines
5.4 KiB
C++

/*
* \brief Generic interface of graphics backend and chunky template
* \date 2005-10-24
* \author Norman Feske <norman.feske@genode-labs.com>
*/
/*
* Copyright (C) 2005-2017 Genode Labs GmbH
*
* This file is part of the Genode OS framework, which is distributed
* under the terms of the GNU Affero General Public License version 3.
*/
#ifndef _INCLUDE__SCOUT__CANVAS_H_
#define _INCLUDE__SCOUT__CANVAS_H_
#include <base/allocator.h>
#include <scout/texture_allocator.h>
#include <os/pixel_rgba.h>
#include <util/color.h>
#include <util/dither_matrix.h>
#include <nitpicker_gfx/texture_painter.h>
#include <nitpicker_gfx/text_painter.h>
#include <nitpicker_gfx/box_painter.h>
#include <scout_gfx/icon_painter.h>
#include <scout_gfx/sky_texture_painter.h>
#include <scout_gfx/horizontal_shadow_painter.h>
#include <scout_gfx/refracted_icon_painter.h>
namespace Scout {
using Genode::Color;
using Genode::Pixel_rgba;
typedef Text_painter::Font Font;
struct Canvas_base;
template <typename PT> class Canvas;
}
struct Scout::Canvas_base : Texture_allocator
{
virtual ~Canvas_base() { }
virtual Area size() const = 0;
virtual Rect clip() const = 0;
virtual void clip(Rect rect) = 0;
virtual void draw_box(int x, int y, int w, int h, Color c) = 0;
virtual void draw_string(int x, int y, Font *font, Color color,
char const *str, size_t len) = 0;
virtual void draw_horizontal_shadow(Rect rect, int intensity) = 0;
virtual void draw_icon(Rect, Texture_base const &, unsigned alpha) = 0;
virtual void draw_sky_texture(int py,
Sky_texture_painter::Sky_texture_base const &,
bool detail) = 0;
virtual void draw_refracted_icon(Point pos,
Scout::Refracted_icon_painter::Distmap<short> const &distmap,
Texture_base &tmp, Texture_base const &foreground,
bool detail, bool filter_backbuf) = 0;
virtual void draw_texture(Point pos, Texture_base const &texture) = 0;
};
#include <os/texture_rgb888.h>
#include <base/env.h>
template <typename PT>
class Scout::Canvas : public Canvas_base
{
private:
Genode::Allocator &_alloc;
Genode::Surface<PT> _surface;
public:
/**
* Constructor
*
* \param alloc allocator to be used for allocating textures
*/
Canvas(PT *base, Area size, Genode::Allocator &alloc)
: _alloc(alloc), _surface(base, size) { }
Area size() const override { return _surface.size(); }
Rect clip() const override { return _surface.clip(); }
void clip(Rect rect) override { _surface.clip(rect); }
void draw_string(int x, int y, Font *font, Color color, char const *str, size_t len) override
{
char buf[len + 1];
Genode::copy_cstring(buf, str, len + 1);
Text_painter::paint(_surface, Text_painter::Position(x, y), *font, color, buf);
}
void draw_box(int x, int y, int w, int h, Color c) override
{
Box_painter::paint(_surface, Rect(Point(x, y), Area(w, h)), c);
}
void draw_horizontal_shadow(Rect rect, int intensity) override
{
Horizontal_shadow_painter::paint(_surface, rect, intensity);
}
void draw_icon(Rect rect, Texture_base const &icon, unsigned alpha) override
{
Icon_painter::paint(_surface, rect,
static_cast<Texture<PT> const &>(icon), alpha);
}
void draw_sky_texture(int py,
Sky_texture_painter::Sky_texture_base const &texture,
bool detail) override
{
Sky_texture_painter::paint(_surface, py, texture, detail);
}
void draw_refracted_icon(Point pos,
Scout::Refracted_icon_painter::Distmap<short> const &distmap,
Texture_base &tmp, Texture_base const &foreground,
bool detail, bool filter_backbuf) override
{
using namespace Scout;
Refracted_icon_painter::paint(_surface, pos, distmap,
static_cast<Texture<PT> &>(tmp),
static_cast<Texture<PT> const &>(foreground),
detail, filter_backbuf);
}
void draw_texture(Point pos, Texture_base const &texture_base) override
{
Texture<PT> const &texture = static_cast<Texture<PT> const &>(texture_base);
Texture_painter::paint(_surface, texture, Color::black(), pos,
Texture_painter::SOLID, true);
}
Texture_base *alloc_texture(Area size, bool has_alpha) override
{
using namespace Genode;
PT *pixel = (PT *)_alloc.alloc(size.count()*sizeof(PT));
unsigned char *alpha = 0;
if (has_alpha)
alpha = (unsigned char *)_alloc.alloc(size.count());
return new (_alloc) Genode::Texture<PT>(pixel, alpha, size);
}
void free_texture(Texture_base *texture_base) override
{
using namespace Genode;
Texture<PT> *texture = static_cast<Texture<PT> *>(texture_base);
Genode::size_t const num_pixels = texture->size().count();
if (texture->alpha())
_alloc.free(texture->alpha(), num_pixels);
_alloc.free(texture->pixel(), sizeof(PT)*num_pixels);
destroy(_alloc, texture);
}
void set_rgba_texture(Texture_base *texture_base,
unsigned char const *rgba,
size_t len, int y) override
{
Texture<PT> *texture = static_cast<Texture<PT> *>(texture_base);
texture->rgba(rgba, len, y);
}
};
#endif /* _INCLUDE__SCOUT__CANVAS_H_ */