git_clone/thorvg
1
0
Fork 0
mirror of https://github.com/thorvg/thorvg.git synced 2025-06-10 06:34:01 +00:00
Code Issues Projects Releases Packages Wiki Activity Actions 5

sw_engine: preventing a double application of the opacity (#540)

Browse source 
For filled and stroked shapes with a gradient, the opacity
was applied during the composition and during the ctable update.
To prevent this, in case the composition occured, ctable
is updated with the opacity = 255.
This commit is contained in:
Mira Grudzinska 2021-07-19 09:02:10 +02:00 • committed by GitHub
parent 8826394b56
commit 96f22e282d
No known key found for this signature in database
GPG key ID: 4AEE18F83AFDEB23
1 changed files with 18 additions and 25 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

43
src/lib/sw_engine/tvgSwRenderer.cpp
View file

@ -69,18 +69,14 @@ struct SwShapeTask : SwTask
{
if (opacity == 0) return; //Invisible
/* Valid filling & stroking each increases the value by 1.
This value is referenced for compositing shape & stroking. */
bool stroking = false;
bool filling = false;
//Valid Stroking?
uint8_t strokeAlpha = 0;
auto strokeWidth = sdata->strokeWidth();
if (HALF_STROKE(strokeWidth) > 0) {
sdata->strokeColor(nullptr, nullptr, nullptr, &strokeAlpha);
}
bool validStroke = (strokeAlpha > 0) || sdata->strokeFill();
bool visibleStroke = (static_cast<uint32_t>(strokeAlpha * opacity / 255) > 0) || sdata->strokeFill();
bool visibleFill = false;
auto clipRegion = bbox;
//invisible shape turned to visible by alpha.
@ -92,30 +88,28 @@ struct SwShapeTask : SwTask
uint8_t alpha = 0;
sdata->fillColor(nullptr, nullptr, nullptr, &alpha);
alpha = static_cast<uint8_t>(static_cast<uint32_t>(alpha) * opacity / 255);
bool renderShape = (alpha > 0 || sdata->fill());
if (renderShape || validStroke) {
visibleFill = (alpha > 0 || sdata->fill());
if (visibleFill || visibleStroke) {
shapeReset(&shape);
if (!shapePrepare(&shape, sdata, transform, clipRegion, bbox, mpool, tid)) goto err;
if (renderShape) {
/* We assume that if stroke width is bigger than 2,
shape outline below stroke could be full covered by stroke drawing.
Thus it turns off antialising in that condition.
Also, it shouldn't be dash style. */
auto antiAlias = (strokeAlpha == 255 && strokeWidth > 2 && sdata->strokeDash(nullptr) == 0) ? false : true;
if (!shapeGenRle(&shape, sdata, antiAlias, clips.count > 0 ? true : false)) goto err;
filling = true;
}
}
}
//Fill
if (flags & (RenderUpdateFlag::Gradient | RenderUpdateFlag::Transform | RenderUpdateFlag::Color)) {
auto fill = sdata->fill();
if (fill) {
if (visibleFill) {
/* We assume that if stroke width is bigger than 2,
shape outline below stroke could be full covered by stroke drawing.
Thus it turns off antialising in that condition.
Also, it shouldn't be dash style. */
auto antiAlias = (strokeAlpha == 255 && strokeWidth > 2 && sdata->strokeDash(nullptr) == 0) ? false : true;
if (!shapeGenRle(&shape, sdata, antiAlias, clips.count > 0 ? true : false)) goto err;
}
if (auto fill = sdata->fill()) {
auto ctable = (flags & RenderUpdateFlag::Gradient) ? true : false;
if (ctable) shapeResetFill(&shape);
if (!shapeGenFillColors(&shape, fill, transform, surface, opacity, ctable)) goto err;
filling = true;
if (!shapeGenFillColors(&shape, fill, transform, surface, visibleStroke ? 255 : opacity, ctable)) goto err;
} else {
shapeDelFill(&shape);
}
@ -123,15 +117,14 @@ struct SwShapeTask : SwTask
//Stroke
if (flags & (RenderUpdateFlag::Stroke | RenderUpdateFlag::Transform)) {
if (validStroke) {
if (visibleStroke) {
shapeResetStroke(&shape, sdata, transform);
if (!shapeGenStrokeRle(&shape, sdata, transform, clipRegion, bbox, mpool, tid)) goto err;
stroking = true;
if (auto fill = sdata->strokeFill()) {
auto ctable = (flags & RenderUpdateFlag::GradientStroke) ? true : false;
if (ctable) shapeResetStrokeFill(&shape);
if (!shapeGenStrokeFillColors(&shape, fill, transform, surface, opacity, ctable)) goto err;
if (!shapeGenStrokeFillColors(&shape, fill, transform, surface, visibleFill ? 255 : opacity, ctable)) goto err;
} else {
shapeDelStrokeFill(&shape);
}
@ -160,7 +153,7 @@ struct SwShapeTask : SwTask
shapeReset(&shape);
end:
shapeDelOutline(&shape, mpool, tid);
if (stroking && filling && opacity < 255) cmpStroking = true;
if (visibleStroke && visibleFill && opacity < 255) cmpStroking = true;
else cmpStroking = false;
}