polybar/include/cairo/context.hpp

359 lines
9.6 KiB
C++

#pragma once
#include <cairo/cairo-xcb.h>
#include <algorithm>
#include <cmath>
#include <deque>
#include "cairo/font.hpp"
#include "cairo/surface.hpp"
#include "cairo/types.hpp"
#include "cairo/utils.hpp"
#include "common.hpp"
#include "components/logger.hpp"
#include "components/types.hpp"
#include "errors.hpp"
#include "utils/color.hpp"
#include "utils/string.hpp"
POLYBAR_NS
namespace cairo {
/**
* @brief Cairo context
*/
class context {
public:
explicit context(const surface& surface, const logger& log) : m_c(cairo_create(surface)), m_log(log) {
auto status = cairo_status(m_c);
if (status != CAIRO_STATUS_SUCCESS) {
throw application_error(sstream() << "cairo_status(): " << cairo_status_to_string(status));
}
cairo_set_antialias(m_c, CAIRO_ANTIALIAS_GOOD);
}
virtual ~context() {
cairo_destroy(m_c);
}
operator cairo_t*() const {
return m_c;
}
context& operator<<(const surface& s) {
cairo_set_source_surface(m_c, s, 0.0, 0.0);
return *this;
}
context& operator<<(cairo_operator_t o) {
cairo_set_operator(m_c, o);
return *this;
}
context& operator<<(cairo_pattern_t* s) {
cairo_set_source(m_c, s);
return *this;
}
context& operator<<(const unsigned int& c) {
// clang-format off
cairo_set_source_rgba(m_c,
color_util::red_channel<unsigned char>(c) / 255.0,
color_util::green_channel<unsigned char>(c) / 255.0,
color_util::blue_channel<unsigned char>(c) / 255.0,
color_util::alpha_channel<unsigned char>(c) / 255.0);
// clang-format on
return *this;
}
context& operator<<(const abspos& p) {
if (p.clear) {
cairo_new_path(m_c);
}
cairo_move_to(m_c, p.x, p.y);
return *this;
}
context& operator<<(const relpos& p) {
cairo_rel_move_to(m_c, p.x, p.y);
return *this;
}
context& operator<<(const rgba& f) {
cairo_set_source_rgba(m_c, f.r, f.g, f.b, f.a);
return *this;
}
context& operator<<(const rect& f) {
cairo_rectangle(m_c, f.x, f.y, f.w, f.h);
return *this;
}
context& operator<<(const line& l) {
struct line p {
l.x1, l.y1, l.x2, l.y2, l.w
};
snap(&p.x1, &p.y1);
snap(&p.x2, &p.y2);
cairo_move_to(m_c, p.x1, p.y1);
cairo_line_to(m_c, p.x2, p.y2);
cairo_set_line_width(m_c, p.w);
cairo_stroke(m_c);
return *this;
}
context& operator<<(const translate& d) {
cairo_translate(m_c, d.x, d.y);
return *this;
}
context& operator<<(const linear_gradient& l) {
if (l.steps.size() >= 2) {
auto pattern = cairo_pattern_create_linear(l.x1, l.y1, l.x2, l.y2);
*this << pattern;
auto stops = l.steps.size();
auto step = 1.0 / (stops - 1);
auto offset = 0.0;
for (auto&& color : l.steps) {
// clang-format off
cairo_pattern_add_color_stop_rgba(pattern, offset,
color_util::red_channel<unsigned char>(color) / 255.0,
color_util::green_channel<unsigned char>(color) / 255.0,
color_util::blue_channel<unsigned char>(color) / 255.0,
color_util::alpha_channel<unsigned char>(color) / 255.0);
// clang-format on
offset += step;
}
cairo_pattern_destroy(pattern);
}
return *this;
}
context& operator<<(const rounded_corners& c) {
double d = M_PI / 180.0;
cairo_new_sub_path(m_c);
cairo_arc(m_c, c.x + c.w - c.radius.top, c.y + c.radius.top, c.radius.top, -90 * d, 0 * d);
cairo_arc(m_c, c.x + c.w - c.radius.bottom, c.y + c.h - c.radius.bottom, c.radius.bottom, 0 * d, 90 * d);
cairo_arc(m_c, c.x + c.radius.bottom, c.y + c.h - c.radius.bottom, c.radius.bottom, 90 * d, 180 * d);
cairo_arc(m_c, c.x + c.radius.top, c.y + c.radius.top, c.radius.top, 180 * d, 270 * d);
cairo_close_path(m_c);
return *this;
}
context& operator<<(const textblock& t) {
double x, y;
position(&x, &y);
// Prioritize the preferred font
vector<shared_ptr<font>> fns(m_fonts.begin(), m_fonts.end());
if (t.font > 0 && t.font <= std::distance(fns.begin(), fns.end())) {
std::iter_swap(fns.begin(), fns.begin() + t.font - 1);
}
string utf8 = string(t.contents);
utils::unicode_charlist chars;
utils::utf8_to_ucs4((const unsigned char*)utf8.c_str(), chars);
while (!chars.empty()) {
auto remaining = chars.size();
for (auto&& f : fns) {
unsigned int matches;
// Match as many glyphs as possible if the default/preferred font
// is being tested. Otherwise test one glyph at a time against
// the remaining fonts. Roll back to the top of the font list
// when a glyph has been found.
if (f == fns.front() && (matches = f->match(chars)) == 0) {
continue;
} else if (f != fns.front() && (matches = f->match(chars.front())) == 0) {
continue;
}
string subset;
auto end = chars.begin();
while (matches-- && end != chars.end()) {
subset += utf8.substr(end->offset, end->length);
end++;
}
// Use the font
f->use();
// Get subset extents
cairo_text_extents_t extents;
f->textwidth(subset, &extents);
// Draw the background
if (t.bg_rect.h != 0.0) {
save();
cairo_set_operator(m_c, t.bg_operator);
*this << t.bg;
cairo_rectangle(m_c, t.bg_rect.x + *t.x_advance, t.bg_rect.y + *t.y_advance,
t.bg_rect.w + extents.x_advance, t.bg_rect.h);
cairo_fill(m_c);
restore();
}
// Render subset
auto fontextents = f->extents();
f->render(subset, x, y - (fontextents.descent / 2 - fontextents.height / 4) + f->offset());
// Get updated position
position(&x, nullptr);
// Increase position
*t.x_advance += extents.x_advance;
*t.y_advance += extents.y_advance;
chars.erase(chars.begin(), end);
break;
}
if (chars.empty()) {
break;
} else if (remaining != chars.size()) {
continue;
}
char unicode[6]{'\0'};
utils::ucs4_to_utf8(unicode, chars.begin()->codepoint);
m_log.warn("Dropping unmatched character %s (U+%04x)", unicode, chars.begin()->codepoint);
utf8.erase(chars.begin()->offset, chars.begin()->length);
for (auto&& c : chars) {
c.offset -= chars.begin()->length;
}
chars.erase(chars.begin(), ++chars.begin());
}
return *this;
}
context& operator<<(shared_ptr<font>&& f) {
m_fonts.emplace_back(forward<decltype(f)>(f));
return *this;
}
context& save(bool save_point = false) {
if (save_point) {
m_points.emplace_front(make_pair<double, double>(0.0, 0.0));
position(&m_points.front().first, &m_points.front().second);
}
m_activegroups++;
cairo_save(m_c);
return *this;
}
context& restore(bool restore_point = false) {
if (!m_activegroups) {
throw application_error("Unmatched calls to save/restore");
}
m_activegroups--;
cairo_restore(m_c);
if (restore_point && !m_points.empty()) {
*this << abspos{m_points.front().first, m_points.front().first};
m_points.pop_front();
}
return *this;
}
context& paint() {
cairo_paint(m_c);
return *this;
}
context& paint(double alpha) {
cairo_paint_with_alpha(m_c, alpha);
return *this;
}
context& fill(bool preserve = false) {
if (preserve) {
cairo_fill_preserve(m_c);
} else {
cairo_fill(m_c);
}
return *this;
}
context& mask(cairo_pattern_t* pattern) {
cairo_mask(m_c, pattern);
return *this;
}
context& pop(cairo_pattern_t** pattern) {
*pattern = cairo_pop_group(m_c);
return *this;
}
context& push() {
cairo_push_group(m_c);
return *this;
}
context& destroy(cairo_pattern_t** pattern) {
cairo_pattern_destroy(*pattern);
*pattern = nullptr;
return *this;
}
context& clear(bool paint = true) {
cairo_save(m_c);
cairo_set_operator(m_c, CAIRO_OPERATOR_CLEAR);
if (paint) {
cairo_paint(m_c);
} else {
cairo_fill_preserve(m_c);
}
cairo_restore(m_c);
return *this;
}
context& clip(bool preserve = false) {
if (preserve) {
cairo_clip_preserve(m_c);
} else {
cairo_clip(m_c);
cairo_new_path(m_c);
}
return *this;
}
context& clip(const rect& r) {
*this << r;
return clip();
}
context& reset_clip() {
cairo_reset_clip(m_c);
return *this;
}
context& position(double* x, double* y = nullptr) {
if (cairo_has_current_point(m_c)) {
double x_, y_;
x = x != nullptr ? x : &x_;
y = y != nullptr ? y : &y_;
cairo_get_current_point(m_c, x, y);
}
return *this;
}
context& snap(double* x, double* y) {
cairo_user_to_device(m_c, x, y);
*x = static_cast<int>(*x + 0.5);
*y = static_cast<int>(*y + 0.5);
return *this;
}
protected:
cairo_t* m_c;
const logger& m_log;
vector<shared_ptr<font>> m_fonts;
std::deque<pair<double, double>> m_points;
int m_activegroups{0};
};
}
POLYBAR_NS_END