common Picture : Introduce Picture's size setter, getter APIs

* common Picture : Introduce Picture's size setter, getter APIs

If picture or file loaded by picture has an explicit Size(width, height),
it is transformed to fit the size.

inc/thorvg.h

@@ -282,6 +282,9 @@ public:
     Result load(uint32_t* data, uint32_t w, uint32_t h, bool copy) noexcept;
     Result viewbox(float* x, float* y, float* w, float* h) const noexcept;
 
+    Result size(uint32_t w, uint32_t h) noexcept;
+    Result size(uint32_t* w, uint32_t* h) const noexcept;
+
     static std::unique_ptr<Picture> gen() noexcept;
 
     _TVG_DECLARE_PRIVATE(Picture);

src/examples/Svg.cpp

@@ -25,25 +25,8 @@ void svgDirCallback(const char* name, const char* path, void* data)
 
     if (picture->load(buf) != tvg::Result::Success) return;
 
-    float x, y, w, h;
-    picture->viewbox(&x, &y, &w, &h);
-
-    float rate = (SIZE/(w > h ? w : h));
-    picture->scale(rate);
-
-    x *= rate;
-    y *= rate;
-    w *= rate;
-    h *= rate;
-
-    //Center Align ?
-    if (w > h) {
-         y -= (SIZE - h) * 0.5f;
-    } else {
-         x -= (SIZE - w) * 0.5f;
-    }
-
-    picture->translate((count % NUM_PER_LINE) * SIZE - x, SIZE * (count / NUM_PER_LINE) - y);
+    picture->size(SIZE, SIZE);
+    picture->translate((count % NUM_PER_LINE) * SIZE, SIZE * (count / NUM_PER_LINE));
 
     pictures.push_back(move(picture));
 

src/lib/tvgLoader.h

@@ -36,6 +36,10 @@ public:
     float vw = 0;
     float vh = 0;
 
+    uint32_t w = 0; //default size
+    uint32_t h = 0; //default size
+    bool preserveAspect = true; //keep aspect ratio by default.
+
     virtual ~Loader() {}
 
     virtual bool open(const string& path) { /* Not supported */ return false; };

src/lib/tvgPicture.cpp

@@ -73,3 +73,19 @@ Result Picture::viewbox(float* x, float* y, float* w, float* h) const noexcept
     if (pImpl->viewbox(x, y, w, h)) return Result::Success;
     return Result::InsufficientCondition;
 }
+
+
+Result Picture::size(uint32_t w, uint32_t h) noexcept
+{
+    if (pImpl->size(w, h)) return Result::Success;
+    return Result::InsufficientCondition;
+}
+
+
+Result Picture::size(uint32_t* w, uint32_t* h) const noexcept
+{
+    if (w) *w = pImpl->w;
+    if (h) *h = pImpl->h;
+    return Result::Success;
+}
+

src/lib/tvgPictureImpl.h

@@ -38,6 +38,9 @@ struct Picture::Impl
     Picture *picture = nullptr;
     void *edata = nullptr;              //engine data
 
+    uint32_t w = 0, h = 0;
+    bool resizing = false;
+
     Impl(Picture* p) : picture(p)
     {
     }
@@ -56,6 +59,36 @@ struct Picture::Impl
         return false;
     }
 
+    void resize()
+    {
+        uint32_t w = 0, h = 0;
+        if (this->w != 0 && this->h != 0) {
+            w = this->w;
+            h = this->h;
+        }
+        else if (loader->w != 0 && loader->h != 0) {
+            w = loader->w;
+            h = loader->h;
+        }
+        if (w != 0 && h != 0) {
+            auto sx = w / (loader->vw + (loader->vx > 0 ? loader->vx : -1 * loader->vx));
+            auto sy = h / (loader->vh + (loader->vy > 0 ? loader->vy : -1 * loader->vy));
+            if (!loader->preserveAspect) {
+                Matrix m = {sx,  0, -loader->vx,
+                             0, sy, -loader->vy,
+                             0,  0, 1};
+                paint->transform(m);
+            }
+            else {
+                auto scale = sx < sy ? sx : sy;
+                paint->translate(((w - loader->vw) * scale) / 2.0, ((h - loader->vh) * scale) / 2.0);
+                paint->scale(scale);
+                paint->translate(-loader->vx, -loader->vy);
+            }
+            resizing = false;
+        }
+    }
+
     uint32_t reload()
     {
         if (loader) {
@@ -63,6 +96,7 @@ struct Picture::Impl
                 auto scene = loader->scene();
                 if (scene) {
                     paint = scene.release();
+                    resizing = true;
                     loader->close();
                     if (paint) return RenderUpdateFlag::None;
                 }
@@ -80,7 +114,10 @@ struct Picture::Impl
         uint32_t flag = reload();
 
         if (pixels) edata = renderer.prepare(*picture, edata, pixels, transform, opacity, compList, static_cast<RenderUpdateFlag>(pFlag | flag));
-        else if (paint) edata = paint->pImpl->update(renderer, transform, opacity, compList, static_cast<RenderUpdateFlag>(pFlag | flag));
+        else if (paint) {
+            if (resizing) resize();
+            edata = paint->pImpl->update(renderer, transform, opacity, compList, static_cast<RenderUpdateFlag>(pFlag | flag));
+        }
         return edata;
     }
 
@@ -101,6 +138,14 @@ struct Picture::Impl
         return true;
     }
 
+    bool size(uint32_t w, uint32_t h)
+    {
+        this->w = w;
+        this->h = h;
+        resizing = true;
+        return true;
+    }
+
     bool bounds(float* x, float* y, float* w, float* h)
     {
         if (!paint) return false;

src/loaders/svg/tvgSvgLoader.cpp

@@ -2466,10 +2466,15 @@ bool SvgLoader::header()
 
     if (loaderData.doc && loaderData.doc->type == SvgNodeType::Doc) {
         //Return the brief resource info such as viewbox:
-        this->vx = loaderData.doc->node.doc.vx;
-        this->vy = loaderData.doc->node.doc.vy;
-        this->vw = loaderData.doc->node.doc.vw;
-        this->vh = loaderData.doc->node.doc.vh;
+        vx = loaderData.doc->node.doc.vx;
+        vy = loaderData.doc->node.doc.vy;
+        vw = loaderData.doc->node.doc.vw;
+        vh = loaderData.doc->node.doc.vh;
+
+        w = loaderData.doc->node.doc.w;
+        h = loaderData.doc->node.doc.h;
+
+        preserveAspect = loaderData.doc->node.doc.preserveAspect;
     } else {
         //LOG: No SVG File. There is no <svg/>
         return false;

src/loaders/svg/tvgSvgSceneBuilder.cpp

@@ -384,10 +384,5 @@ unique_ptr<Scene> SvgSceneBuilder::build(SvgNode* node)
 {
     if (!node || (node->type != SvgNodeType::Doc)) return nullptr;
 
-    viewBox.x = node->node.doc.vx;
-    viewBox.y = node->node.doc.vy;
-    viewBox.w = node->node.doc.vw;
-    viewBox.h = node->node.doc.vh;
-    preserveAspect = node->node.doc.preserveAspect;
-    return _sceneBuildHelper(node, viewBox.x, viewBox.y, viewBox.w, viewBox.h, 255);
+    return _sceneBuildHelper(node, node->node.doc.vx, node->node.doc.vy, node->node.doc.vw, node->node.doc.vh, 255);
 }

src/loaders/svg/tvgSvgSceneBuilder.h

@@ -27,13 +27,6 @@
 
 class SvgSceneBuilder
 {
-private:
-    struct {
-        int x, y;
-        uint32_t w, h;
-    } viewBox = {0, 0, 0, 0};
-    bool     preserveAspect = false;
-
 public:
     SvgSceneBuilder();
     ~SvgSceneBuilder();