Skip to content

Commit

Permalink
Fixes the sixel aspect ratio.
Browse files Browse the repository at this point in the history
  • Loading branch information
@Utkarsh-khambra
Utkarsh-khambra committed Sep 25, 2022
1 parent 6c3b7fa commit 7ecef09
Show file tree
Hide file tree
Showing 4 changed files with 72 additions and 43 deletions.
4 changes: 2 additions & 2 deletions src/terminal/Screen.cpp
View file
Original file line number Diff line number Diff line change
Expand Up @@ -3413,8 +3413,8 @@ unique_ptr<ParserExtension> Screen<Cell>::hookSixel(Sequence const& _seq)
case 3: return 3;
case 2: return 5;
case 1:
case 0:
default: return 2;
case 0: return 2;
default: return 1;
}
}(Pa);

Expand Down
70 changes: 40 additions & 30 deletions src/terminal/SixelParser.cpp
View file
Original file line number Diff line number Diff line change
Expand Up @@ -23,6 +23,7 @@ using std::vector;

// VT 340 sixel protocol is defined here: https://vt100.net/docs/vt3xx-gp/chapter14.html

using namespace std;
namespace terminal
{

Expand Down Expand Up @@ -289,13 +290,17 @@ void SixelParser::leaveState()
case State::RepeatIntroducer: break;

case State::RasterSettings:
if (params_.size() == 4)
if (params_.size() > 1 && params_.size() < 5)
{
auto const pan = params_[0];
auto const pad = params_[1];
auto const xPixels = Width(params_[2]);
auto const yPixels = Height(params_[3]);
events_.setRaster((int) pan, (int) pad, ImageSize { xPixels, yPixels });

auto const imageSize =
params_.size() > 2
? optional<ImageSize> { ImageSize { Width(params_[2]), Height(params_[3]) } }
: std::nullopt;

events_.setRaster(pan, pad, imageSize);
state_ = State::Ground;
}
break;
Expand Down Expand Up @@ -371,7 +376,9 @@ SixelImageBuilder::SixelImageBuilder(ImageSize _maxSize,
buffer_(maxSize_.area() * 4),
sixelCursor_ {},
currentColor_ { 0 },
aspectRatio_ { _aspectVertical, _aspectHorizontal }
aspectRatio_(static_cast<unsigned int>(
std::ceil(static_cast<float>(_aspectVertical) / static_cast<float>(_aspectHorizontal)))),
sixelBandHeight_(6 * aspectRatio_)
{
clear(_backgroundColor);
}
Expand Down Expand Up @@ -408,23 +415,20 @@ void SixelImageBuilder::write(CellLocation const& _coord, RGBColor const& _value
if (!explicitSize_)
{
if (unbox<int>(_coord.line) >= unbox<int>(size_.height))
size_.height = Height::cast_from(_coord.line + 1);
size_.height = Height::cast_from(_coord.line.as<unsigned int>() + aspectRatio_);
if (unbox<int>(_coord.column) >= unbox<int>(size_.width))
size_.width = Width::cast_from(_coord.column + 1);
}

for (auto i = 0; i < aspectRatio_.nominator; ++i)
for (unsigned int i = 0; i < aspectRatio_; ++i)
{
auto const base = unbox<unsigned>(_coord.line + i)
* unbox<unsigned>((explicitSize_ ? size_.width : maxSize_.width)) * 4
+ unbox<unsigned>(_coord.column) * 4;
for (auto j = 0; j < aspectRatio_.denominator; ++j)
{
buffer_[base + 0 + 4 * static_cast<unsigned int>(j)] = _value.red;
buffer_[base + 1 + 4 * static_cast<unsigned int>(j)] = _value.green;
buffer_[base + 2 + 4 * static_cast<unsigned int>(j)] = _value.blue;
buffer_[base + 3 + 4 * static_cast<unsigned int>(j)] = 0xFF;
}
auto const base = (_coord.line.as<unsigned int>() + i)
* unbox<unsigned int>((explicitSize_ ? size_.width : maxSize_.width)) * 4u
+ unbox<unsigned int>(_coord.column) * 4u;
buffer_[base + 0] = _value.red;
buffer_[base + 1] = _value.green;
buffer_[base + 2] = _value.blue;
buffer_[base + 3] = 0xFF;
}
}
}
Expand All @@ -447,19 +451,25 @@ void SixelImageBuilder::rewind()
void SixelImageBuilder::newline()
{
sixelCursor_.column = {};
if (unbox<int>(sixelCursor_.line) + 6 < unbox<int>(explicitSize_ ? size_.height : maxSize_.height))
sixelCursor_.line.value += 6;
if (unbox<unsigned int>(sixelCursor_.line) + sixelBandHeight_
< unbox<unsigned int>(explicitSize_ ? size_.height : maxSize_.height))
sixelCursor_.line = LineOffset::cast_from(sixelCursor_.line.as<unsigned int>() + sixelBandHeight_);
}

void SixelImageBuilder::setRaster(int _pan, int _pad, ImageSize _imageSize)
void SixelImageBuilder::setRaster(unsigned int _pan, unsigned int _pad, optional<ImageSize> _imageSize)
{
aspectRatio_.nominator = _pan;
aspectRatio_.denominator = _pad;
size_.width = clamp(_imageSize.width, Width(0), maxSize_.width);
size_.height = clamp(_imageSize.height, Height(0), maxSize_.height);

buffer_.resize(size_.area() * static_cast<size_t>(_pad * _pan) * 4);
explicitSize_ = true;
if (_pad != 0)
aspectRatio_ = max(
1u, static_cast<unsigned int>(std::ceil(static_cast<float>(_pan) / static_cast<float>(_pad))));
sixelBandHeight_ = 6 * aspectRatio_;
if (_imageSize)
{
_imageSize->height = Height::cast_from(_imageSize->height.value * aspectRatio_);
size_.width = clamp(_imageSize->width, Width(0), maxSize_.width);
size_.height = clamp(_imageSize->height, Height(0), maxSize_.height);
buffer_.resize(size_.area() * 4);
explicitSize_ = true;
}
}

void SixelImageBuilder::render(int8_t _sixel)
Expand All @@ -468,9 +478,9 @@ void SixelImageBuilder::render(int8_t _sixel)
auto const x = sixelCursor_.column;
if (unbox<int>(x) < unbox<int>((explicitSize_ ? size_.width : maxSize_.width)))
{
for (int i = 0; i < 6; ++i)
for (unsigned int i = 0; i < 6; ++i)
{
auto const y = sixelCursor_.line + i;
auto const y = sixelCursor_.line + static_cast<int>(i * aspectRatio_);
auto const pos = CellLocation { y, x };
auto const pin = 1 << i;
auto const pinned = (_sixel & pin) != 0;
Expand All @@ -485,7 +495,7 @@ void SixelImageBuilder::finalize()
{
if (unbox<int>(size_.height) == 1)
{
size_.height = Height::cast_from(sixelCursor_.line * aspectRatio_.nominator);
size_.height = Height::cast_from(sixelCursor_.line.as<unsigned int>() * aspectRatio_);
buffer_.resize(size_.area() * 4);
return;
}
Expand Down
18 changes: 9 additions & 9 deletions src/terminal/SixelParser.h
View file
Original file line number Diff line number Diff line change
Expand Up @@ -21,6 +21,7 @@

#include <array>
#include <memory>
#include <optional>
#include <string_view>
#include <vector>

Expand Down Expand Up @@ -71,7 +72,7 @@ class SixelParser: public ParserExtension

/// Defines the aspect ratio (pan / pad = aspect ratio) and image dimensions in pixels for
/// the upcoming pixel data.
virtual void setRaster(int _pan, int _pad, ImageSize _imageSize) = 0;
virtual void setRaster(unsigned int _pan, unsigned int _pad, std::optional<ImageSize> _imageSize) = 0;

/// renders a given sixel at the current sixel-cursor position.
virtual void render(int8_t _sixel) = 0;
Expand Down Expand Up @@ -162,8 +163,7 @@ class SixelImageBuilder: public SixelParser::Events

[[nodiscard]] ImageSize maxSize() const noexcept { return maxSize_; }
[[nodiscard]] ImageSize size() const noexcept { return size_; }
[[nodiscard]] int aspectRatioNominator() const noexcept { return aspectRatio_.nominator; }
[[nodiscard]] int aspectRatioDenominator() const noexcept { return aspectRatio_.denominator; }
[[nodiscard]] unsigned int aspectRatio() const noexcept { return aspectRatio_; }
[[nodiscard]] RGBColor currentColor() const noexcept { return colors_->at(currentColor_); }

[[nodiscard]] RGBAColor at(CellLocation _coord) const noexcept;
Expand All @@ -177,7 +177,7 @@ class SixelImageBuilder: public SixelParser::Events
void useColor(unsigned _index) override;
void rewind() override;
void newline() override;
void setRaster(int _pan, int _pad, ImageSize _imageSize) override;
void setRaster(unsigned int _pan, unsigned int _pad, std::optional<ImageSize> _imageSize) override;
void render(int8_t _sixel) override;
void finalize() override;

Expand All @@ -193,12 +193,12 @@ class SixelImageBuilder: public SixelParser::Events
Buffer buffer_; /// RGBA buffer
CellLocation sixelCursor_;
unsigned currentColor_;
struct
{
int nominator;
int denominator;
} aspectRatio_;
bool explicitSize_ = false;
// This is an int because vt3xx takes the given ratio pan/pad and rounds up the ratio
// to nearest integers. So 1:3 = 0.33 and it becomes 1;
unsigned int aspectRatio_;
// Height of sixel band in pixels
unsigned int sixelBandHeight_;
};

} // namespace terminal
23 changes: 21 additions & 2 deletions src/terminal/SixelParser_test.cpp
View file
Original file line number Diff line number Diff line change
Expand Up @@ -195,10 +195,29 @@ TEST_CASE("SixelParser.raster", "[sixel]")
sp.done();

CHECK(ib.sixelCursor() == CellLocation { LineOffset(0), ColumnOffset(0) });
CHECK(ib.aspectRatioNominator() == 12);
CHECK(ib.aspectRatioDenominator() == 34);
CHECK(ib.aspectRatio() == 1);
CHECK(*ib.size().width == 32);
CHECK(*ib.size().height == 24);
sp.parseFragment("\"12;34");
sp.done();
CHECK(ib.sixelCursor() == CellLocation { LineOffset(0), ColumnOffset(0) });
CHECK(ib.aspectRatio() == 1);
sp.parseFragment("\"");
sp.done();
CHECK(ib.sixelCursor() == CellLocation { LineOffset(0), ColumnOffset(0) });
CHECK(ib.aspectRatio() == 1);
sp.parseFragment("\"0;0");
sp.done();
CHECK(ib.sixelCursor() == CellLocation { LineOffset(0), ColumnOffset(0) });
CHECK(ib.aspectRatio() == 1);
sp.parseFragment("\"5;0");
sp.done();
CHECK(ib.sixelCursor() == CellLocation { LineOffset(0), ColumnOffset(0) });
CHECK(ib.aspectRatio() == 1);
sp.parseFragment("\"15;2");
sp.done();
CHECK(ib.sixelCursor() == CellLocation { LineOffset(0), ColumnOffset(0) });
CHECK(ib.aspectRatio() == 8);
}

TEST_CASE("SixelParser.rep", "[sixel]")
Expand Down

0 comments on commit 7ecef09

Please sign in to comment.