Font improvements

?border and ?outline blend nicer when applied to font glyphs
This commit is contained in:
Kae 2023-06-21 18:59:15 +10:00
parent d08b3c3b22
commit f2e64e1752
5 changed files with 28 additions and 7 deletions

View File

@ -141,10 +141,9 @@ public:
Color& operator+=(Color const& c);
Color& operator*=(Color const& c);
private:
static float toLinear(float in);
static float fromLinear(float in);
private:
Vec4F m_data;
};

View File

@ -87,10 +87,10 @@ unsigned Font::width(String::Char c) {
Image Font::render(String::Char c) {
if (!m_fontImpl)
throw FontException("Font::render called on uninitialzed font.");
throw FontException("Font::render called on uninitialized font.");
FT_UInt glyph_index = FT_Get_Char_Index(m_fontImpl->face, c);
if (FT_Load_Glyph(m_fontImpl->face, glyph_index, FT_LOAD_DEFAULT) != 0)
if (FT_Load_Glyph(m_fontImpl->face, glyph_index, FT_LOAD_FORCE_AUTOHINT) != 0)
return {};
/* convert to an anti-aliased bitmap */

View File

@ -224,6 +224,7 @@ ImageOperation imageOperationFromString(String const& string) {
else
operation.endColor = operation.startColor;
operation.outlineOnly = type == "outline";
operation.includeTransparent = false; // Currently just here for anti-aliased fonts
return operation;
@ -476,7 +477,8 @@ Image processImageOperations(List<ImageOperation> const& operations, Image image
borderImage.forEachPixel([&op, &image, &borderImageSize](int x, int y, Vec4B& pixel) {
int pixels = op->pixels;
if (pixel[3] == 0) {
bool includeTransparent = op->includeTransparent;
if (pixel[3] == 0 || (includeTransparent && pixel[3] != 255)) {
int dist = std::numeric_limits<int>::max();
for (int j = -pixels; j < pixels + 1; j++) {
for (int i = -pixels; i < pixels + 1; i++) {
@ -493,7 +495,21 @@ Image processImageOperations(List<ImageOperation> const& operations, Image image
if (dist < std::numeric_limits<int>::max()) {
float percent = (dist - 1) / (2.0f * pixels - 1);
pixel = Vec4B(Vec4F(op->startColor) * (1 - percent) + Vec4F(op->endColor) * percent);
Vec4F color = (Vec4F(op->startColor) * ((1.0f - percent) / 255.0f)) + (Vec4F(op->endColor) * (percent / 255.0f));
color.clamp(0.0f, 1.0f);
if (pixel[3] != 0) {
float pixelA = byteToFloat(pixel[3]);
if (op->outlineOnly)
color[3] *= (1.0f - pixelA);
else {
float colorA = pixelA * (1.0f - color[3]);
color[0] = Color::fromLinear((Color::toLinear(color[0]) * colorA) + (Color::toLinear(byteToFloat(pixel[0])) * pixelA));
color[1] = Color::fromLinear((Color::toLinear(color[1]) * colorA) + (Color::toLinear(byteToFloat(pixel[1])) * pixelA));
color[2] = Color::fromLinear((Color::toLinear(color[2]) * colorA) + (Color::toLinear(byteToFloat(pixel[2])) * pixelA));
color[3] += colorA;
}
}
pixel = Vec4B(color.piecewiseMultiply(Vec4F::filled(255.0f)));
}
} else if (op->outlineOnly) {
pixel = Vec4B(0, 0, 0, 0);

View File

@ -102,6 +102,7 @@ struct BorderImageOperation {
Vec4B startColor;
Vec4B endColor;
bool outlineOnly;
bool includeTransparent;
};
struct ScaleImageOperation {

View File

@ -21,7 +21,12 @@ const FontTextureGroup::GlyphTexture& FontTextureGroup::glyphTexture(String::Cha
Image image = m_font->render(c);
if (!processingDirectives.empty()) {
Vec2F preSize = Vec2F(image.size());
image = processImageOperations(parseImageOperations(processingDirectives), image);
auto imageOperations = parseImageOperations(processingDirectives);
for (auto& imageOp : imageOperations) {
if (auto border = imageOp.ptr<BorderImageOperation>())
border->includeTransparent = true;
}
image = processImageOperations(imageOperations, image);
res.first->second.processingOffset = preSize - Vec2F(image.size());
}
else