api: revise the api for v1.0

- refactored the Fill matrix to hold internal data statically.
- refactored for clean & neat the raster engine / svg loader logic.

API Modification:
 - Matrix Fill::transform() const -> Matrix& Fill::transform() const

issue: https://github.com/thorvg/thorvg/issues/1372

inc/thorvg.h

@@ -546,7 +546,7 @@ public:
      *
      * @return The augmented transformation matrix.
      */
-    Matrix transform() const noexcept;
+    Matrix& transform() const noexcept;
 
     /**
      * @brief Creates a copy of the Fill object.

src/loaders/svg/tvgSvgSceneBuilder.cpp

@@ -92,9 +92,8 @@ static unique_ptr<LinearGradient> _applyLinearGradientProperty(SvgStyleGradient*
     Fill::ColorStop* stops;
     int stopCount = 0;
     auto fillGrad = LinearGradient::gen();
-
-    bool isTransform = (g->transform ? true : false);
-    Matrix finalTransform = {1, 0, 0, 0, 1, 0, 0, 0, 1};
+    auto isTransform = (g->transform ? true : false);
+    auto& finalTransform = fillGrad->transform();
     if (isTransform) finalTransform = *g->transform;
 
     if (g->userSpace) {
@@ -105,13 +104,8 @@ static unique_ptr<LinearGradient> _applyLinearGradientProperty(SvgStyleGradient*
     } else {
         Matrix m = {vBox.w, 0, vBox.x, 0, vBox.h, vBox.y, 0, 0, 1};
         if (isTransform) _transformMultiply(&m, &finalTransform);
-        else {
-            finalTransform = m;
-            isTransform = true;
+        else finalTransform = m;
     }
-    }
-
-    if (isTransform) fillGrad->transform(finalTransform);
 
     fillGrad->linear(g->linear->x1, g->linear->y1, g->linear->x2, g->linear->y2);
     fillGrad->spread(g->spread);
@@ -147,9 +141,8 @@ static unique_ptr<RadialGradient> _applyRadialGradientProperty(SvgStyleGradient*
     Fill::ColorStop *stops;
     int stopCount = 0;
     auto fillGrad = RadialGradient::gen();
-
-    bool isTransform = (g->transform ? true : false);
-    Matrix finalTransform = {1, 0, 0, 0, 1, 0, 0, 0, 1};
+    auto isTransform = (g->transform ? true : false);
+    auto& finalTransform = fillGrad->transform();
     if (isTransform) finalTransform = *g->transform;
 
     if (g->userSpace) {
@@ -164,13 +157,8 @@ static unique_ptr<RadialGradient> _applyRadialGradientProperty(SvgStyleGradient*
     } else {
         Matrix m = {vBox.w, 0, vBox.x, 0, vBox.h, vBox.y, 0, 0, 1};
         if (isTransform) _transformMultiply(&m, &finalTransform);
-        else {
-            finalTransform = m;
-            isTransform = true;
+        else finalTransform = m;
     }
-    }
-
-    if (isTransform) fillGrad->transform(finalTransform);
 
     P(fillGrad)->radial(g->radial->cx, g->radial->cy, g->radial->r, g->radial->fx, g->radial->fy, g->radial->fr);
     fillGrad->spread(g->spread);

src/renderer/gl_engine/tvgGlRenderer.cpp

@@ -288,27 +288,15 @@ void GlRenderer::drawPrimitive(GlShape& sdata, const Fill* fill, RenderUpdateFla
     {
         const auto& matrix = sdata.geometry->getTransformMatrix();
 
-        auto gradientTransform = fill->transform();
         float invMat4[16];
-        if (!identity(const_cast<const Matrix*>(&gradientTransform))) {
-            Matrix inv{};
-            inverse(&gradientTransform  , &inv);
-
+        Matrix inv;
+        inverse(&fill->transform(), &inv);
         GET_MATRIX44(inv, invMat4);
-        } else {
-            memset(invMat4, 0, 16 * sizeof(float));
-            invMat4[0] = 1.f;
-            invMat4[5] = 1.f;
-            invMat4[10] = 1.f;
-            invMat4[15] = 1.f;
-        }
 
         float matrix44[16];
-
         currentPass()->getMatrix(matrix44, matrix);
 
         uint32_t loc = task->getProgram()->getUniformBlockIndex("Matrix");
-
         uint32_t viewOffset = mGpuBuffer->push(matrix44, 16 * sizeof(float), true);
 
         task->addBindResource(GlBindingResource{

src/renderer/sw_engine/tvgSwFill.cpp

@@ -207,7 +207,7 @@ static bool _updateColorTable(SwFill* fill, const Fill* fdata, const SwSurface*
 }
 
 
-bool _prepareLinear(SwFill* fill, const LinearGradient* linear, const Matrix& transform)
+bool _prepareLinear(SwFill* fill, const LinearGradient* linear, const Matrix& pTransform)
 {
     float x1, x2, y1, y2;
     if (linear->linear(&x1, &y1, &x2, &y2) != Result::Success) return false;
@@ -227,32 +227,22 @@ bool _prepareLinear(SwFill* fill, const LinearGradient* linear, const Matrix& tr
     fill->linear.dy /= len;
     fill->linear.offset = -fill->linear.dx * x1 - fill->linear.dy * y1;
 
-    auto gradTransform = linear->transform();
-    bool isTransformation = !identity((const Matrix*)(&gradTransform));
+    auto transform = pTransform * linear->transform();
 
-    if (isTransformation) {
-        gradTransform = transform * gradTransform;
-    } else {
-        gradTransform = transform;
-        isTransformation = true;
-    }
+    Matrix itransform;
+    if (!inverse(&transform, &itransform)) return false;
 
-    if (isTransformation) {
-        Matrix invTransform;
-        if (!inverse(&gradTransform, &invTransform)) return false;
-
-        fill->linear.offset += fill->linear.dx * invTransform.e13 + fill->linear.dy * invTransform.e23;
+    fill->linear.offset += fill->linear.dx * itransform.e13 + fill->linear.dy * itransform.e23;
 
     auto dx = fill->linear.dx;
-        fill->linear.dx = dx * invTransform.e11 + fill->linear.dy * invTransform.e21;
-        fill->linear.dy = dx * invTransform.e12 + fill->linear.dy * invTransform.e22;
-    }
+    fill->linear.dx = dx * itransform.e11 + fill->linear.dy * itransform.e21;
+    fill->linear.dy = dx * itransform.e12 + fill->linear.dy * itransform.e22;
 
     return true;
 }
 
 
-bool _prepareRadial(SwFill* fill, const RadialGradient* radial, const Matrix& transform)
+bool _prepareRadial(SwFill* fill, const RadialGradient* radial, const Matrix& pTransform)
 {
     auto cx = P(radial)->cx;
     auto cy = P(radial)->cy;
@@ -294,29 +284,18 @@ bool _prepareRadial(SwFill* fill, const RadialGradient* radial, const Matrix& tr
 
     if (fill->radial.a > 0) fill->radial.invA = 1.0f / fill->radial.a;
 
-    auto gradTransform = radial->transform();
-    bool isTransformation = !identity((const Matrix*)(&gradTransform));
+    auto transform = pTransform * radial->transform();
 
-    if (isTransformation) gradTransform = transform * gradTransform;
-    else {
-        gradTransform = transform;
-        isTransformation = true;
-    }
+    Matrix itransform;
+    if (!inverse(&transform, &itransform)) return false;
+
+    fill->radial.a11 = itransform.e11;
+    fill->radial.a12 = itransform.e12;
+    fill->radial.a13 = itransform.e13;
+    fill->radial.a21 = itransform.e21;
+    fill->radial.a22 = itransform.e22;
+    fill->radial.a23 = itransform.e23;
 
-    if (isTransformation) {
-        Matrix invTransform;
-        if (!inverse(&gradTransform, &invTransform)) return false;
-        fill->radial.a11 = invTransform.e11;
-        fill->radial.a12 = invTransform.e12;
-        fill->radial.a13 = invTransform.e13;
-        fill->radial.a21 = invTransform.e21;
-        fill->radial.a22 = invTransform.e22;
-        fill->radial.a23 = invTransform.e23;
-    } else {
-        fill->radial.a11 = fill->radial.a22 = 1.0f;
-        fill->radial.a12 = fill->radial.a13 = 0.0f;
-        fill->radial.a21 = fill->radial.a23 = 0.0f;
-    }
     return true;
 }
 

src/renderer/tvgFill.cpp

@@ -134,18 +134,14 @@ FillSpread Fill::spread() const noexcept
 
 Result Fill::transform(const Matrix& m) noexcept
 {
-    if (!pImpl->transform) {
-        pImpl->transform = static_cast<Matrix*>(malloc(sizeof(Matrix)));
-    }
-    *pImpl->transform = m;
+    pImpl->transform = m;
     return Result::Success;
 }
 
 
-Matrix Fill::transform() const noexcept
+Matrix& Fill::transform() const noexcept
 {
-    if (pImpl->transform) return *pImpl->transform;
-    return {1, 0, 0, 0, 1, 0, 0, 0, 1};
+    return pImpl->transform;
 }
 
 

src/renderer/tvgFill.h

@@ -51,16 +51,15 @@ struct FillDup : DuplicateMethod<Fill>
 struct Fill::Impl
 {
     ColorStop* colorStops = nullptr;
-    Matrix* transform = nullptr;
+    Matrix transform = {1.0f, 0.0f, 0.0f, 0.0f, 1.0f, 0.0f, 0.0f, 0.0f, 1.0f};
     uint32_t cnt = 0;
-    FillSpread spread;
     DuplicateMethod<Fill>* dup = nullptr;
+    FillSpread spread;
 
     ~Impl()
     {
         delete(dup);
         free(colorStops);
-        free(transform);
     }
 
     void method(DuplicateMethod<Fill>* dup)
@@ -71,16 +70,13 @@ struct Fill::Impl
     Fill* duplicate()
     {
         auto ret = dup->duplicate();
-        if (!ret) return nullptr;
 
         ret->pImpl->cnt = cnt;
         ret->pImpl->spread = spread;
         ret->pImpl->colorStops = static_cast<ColorStop*>(malloc(sizeof(ColorStop) * cnt));
         memcpy(ret->pImpl->colorStops, colorStops, sizeof(ColorStop) * cnt);
-        if (transform) {
-            ret->pImpl->transform = static_cast<Matrix*>(malloc(sizeof(Matrix)));
-            *ret->pImpl->transform = *transform;
-        }
+        ret->pImpl->transform = transform;
+
         return ret;
     }
 };

src/renderer/wg_engine/tvgWgRenderData.cpp

@@ -213,10 +213,9 @@ void WgRenderSettings::update(WgContext& context, const Fill* fill, const uint8_
     if ((flags & (RenderUpdateFlag::Gradient)) && fill) {
         rasterType = WgRenderRasterType::Gradient;
         // get gradient transfrom matrix
-        Matrix fillTransform = fill->transform();
         Matrix invFillTransform;
         WgShaderTypeMat4x4f gradientTrans; // identity by default
-        if (inverse(&fillTransform, &invFillTransform))
+        if (inverse(&fill->transform(), &invFillTransform))
             gradientTrans.update(invFillTransform);
         // get gradient rasterisation settings
         WgShaderTypeGradient gradient;