Prevent pattern from being downscaled below its original size #247

Clamp `xScale` and `yScale` to a minimum of `1` when rendering patterns, ensuring
the bitmap is never scaled below its native resolution. This avoids
distortion and visual artifacts caused by downscaling at very small pattern
scales while maintaining correct tiling and alignment.

Author: sammycage

source/svgpaintelement.cpp

@@ -289,13 +289,10 @@ bool SVGPatternElement::applyPaint(SVGRenderState& state, float opacity) const
     }
 
     auto currentTransform = attributes.patternTransform() * state.currentTransform();
-    auto xScale = currentTransform.xScale();
-    auto yScale = currentTransform.yScale();
+    auto xScale = std::max(1.f, currentTransform.xScale());
+    auto yScale = std::max(1.f, currentTransform.yScale());
 
-    auto tileWidth = std::round(patternRect.w * xScale);
-    auto tileHeight = std::round(patternRect.h * yScale);
-
-    auto patternImage = Canvas::create(0, 0, tileWidth, tileHeight);
+    auto patternImage = Canvas::create(0, 0, patternRect.w * xScale, patternRect.h * yScale);
     auto patternImageTransform = Transform::scaled(xScale, yScale);
 
     const auto& viewBoxRect = attributes.viewBox();
@@ -312,7 +309,7 @@ bool SVGPatternElement::applyPaint(SVGRenderState& state, float opacity) const
 
     auto patternTransform = attributes.patternTransform();
     patternTransform.translate(patternRect.x, patternRect.y);
-    patternTransform.scale(patternRect.w / patternImage->width(), patternRect.h / patternImage->height());
+    patternTransform.scale(1.f / xScale, 1.f / yScale);
     state->setTexture(*patternImage, TextureType::Tiled, opacity, patternTransform);
     return true;
 }