Tie the ImageCairo to graphics context

dgl/Image.hpp

@@ -115,7 +115,7 @@ public:
 
 protected:
    /** @internal */
-    void _drawAt(const Point<int>& pos, const GraphicsContext& gc) override;
+    void _drawAt(const Point<int>& pos) override;
 
 private:
     GLenum fFormat;
@@ -144,13 +144,18 @@ public:
       @note If @takeReference is true, this increments the reference counter
       of the cairo surface.
     */
-    ImageCairo(cairo_surface_t* surface, bool takeReference) noexcept;
+    ImageCairo(cairo_surface_t* surface, bool takeReference, const GraphicsContext* gc) noexcept;
 
    /**
       Constructor using another image data.
     */
     ImageCairo(const ImageCairo& image) noexcept;
 
+   /**
+      Constructor using another image data, transferring to a different graphics context.
+    */
+    ImageCairo(const ImageCairo& image, const GraphicsContext* gc) noexcept;
+
    /**
       Destructor.
       @note Decrements the reference counter of the cairo surface.
@@ -161,7 +166,7 @@ public:
       Load image data from memory.
       @note @a rawData must remain valid for the lifetime of this Image.
     */
-    void loadFromPng(const char* const pngData, const uint pngSize) noexcept;
+    void loadFromPng(const char* const pngData, const uint pngSize, const GraphicsContext* gc) noexcept;
 
    /**
       Extract a part of the image bounded by the given rectangle.
@@ -191,10 +196,11 @@ public:
 
 protected:
    /** @internal */
-    void _drawAt(const Point<int>& pos, const GraphicsContext& gc) override;
+    void _drawAt(const Point<int>& pos) override;
 
 private:
     cairo_surface_t* fSurface;
+    const GraphicsContext* fGc;
 };
 #endif // DGL_CAIRO
 

dgl/ImageBase.hpp

@@ -91,34 +91,17 @@ public:
    /**
       Draw this image at (0, 0) point.
     */
-    void draw(const GraphicsContext& gc);
+    void draw();
 
    /**
       Draw this image at (x, y) point.
     */
-    void drawAt(const int x, const int y, const GraphicsContext& gc);
+    void drawAt(const int x, const int y);
 
    /**
       Draw this image at position @a pos.
     */
-    void drawAt(const Point<int>& pos, const GraphicsContext& gc);
-
-#ifdef DGL_OPENGL
-   /**
-      Draw this image at (0, 0) point.
-    */
-    DISTRHO_DEPRECATED void draw();
-
-   /**
-      Draw this image at (x, y) point.
-    */
-    DISTRHO_DEPRECATED void drawAt(const int x, const int y);
-
-   /**
-      Draw this image at position @a pos.
-    */
-    DISTRHO_DEPRECATED void drawAt(const Point<int>& pos);
-#endif
+    void drawAt(const Point<int>& pos);
 
    /**
       TODO document this.
@@ -129,7 +112,7 @@ public:
 
 protected:
    /** @internal */
-    virtual void _drawAt(const Point<int>& pos, const GraphicsContext& gc) = 0;
+    virtual void _drawAt(const Point<int>& pos) = 0;
 
     const char* fRawData;
     Size<uint> fSize;

dgl/src/Image.cpp

@@ -115,7 +115,7 @@ ImageOpenGL& ImageOpenGL::operator=(const Image& image) noexcept
     return *this;
 }
 
-void ImageOpenGL::_drawAt(const Point<int>& pos, const GraphicsContext& gc)
+void ImageOpenGL::_drawAt(const Point<int>& pos)
 {
     if (fTextureId == 0 || ! isValid())
         return;
@@ -146,9 +146,6 @@ void ImageOpenGL::_drawAt(const Point<int>& pos, const GraphicsContext& gc)
 
     glBindTexture(GL_TEXTURE_2D, 0);
     glDisable(GL_TEXTURE_2D);
-
-    // unused
-    (void)gc;
 }
 #endif // DGL_OPENGL
 
@@ -159,12 +156,14 @@ void ImageOpenGL::_drawAt(const Point<int>& pos, const GraphicsContext& gc)
 
 ImageCairo::ImageCairo() noexcept
     : ImageBase(),
-      fSurface(nullptr)
+      fSurface(nullptr),
+      fGc(nullptr)
 {
 }
 
-ImageCairo::ImageCairo(cairo_surface_t* surface, bool takeReference) noexcept
-    : fSurface(surface)
+ImageCairo::ImageCairo(cairo_surface_t* surface, bool takeReference, const GraphicsContext* gc) noexcept
+    : fSurface(surface),
+      fGc(gc)
 {
     if (takeReference)
         cairo_surface_reference(surface);
@@ -176,7 +175,19 @@ ImageCairo::ImageCairo(cairo_surface_t* surface, bool takeReference) noexcept
 
 ImageCairo::ImageCairo(const ImageCairo& image) noexcept
     : ImageBase(*this),
-      fSurface(cairo_surface_reference(image.fSurface))
+      fSurface(cairo_surface_reference(image.fSurface)),
+      fGc(image.fGc)
+{
+    cairo_surface_t* surface = fSurface;
+    fRawData = (const char*)cairo_image_surface_get_data(surface);
+    fSize.setWidth(cairo_image_surface_get_width(surface));
+    fSize.setHeight(cairo_image_surface_get_height(surface));
+}
+
+ImageCairo::ImageCairo(const ImageCairo& image, const GraphicsContext* gc) noexcept
+    : ImageBase(*this),
+      fSurface(cairo_surface_reference(image.fSurface)),
+      fGc(gc)
 {
     cairo_surface_t* surface = fSurface;
     fRawData = (const char*)cairo_image_surface_get_data(surface);
@@ -210,7 +221,7 @@ static cairo_status_t readSomePngData(void *closure,
     return CAIRO_STATUS_SUCCESS;
 }
 
-void ImageCairo::loadFromPng(const char* const pngData, const uint pngSize) noexcept
+void ImageCairo::loadFromPng(const char* const pngData, const uint pngSize, const GraphicsContext* gc) noexcept
 {
     PngReaderData readerData;
     readerData.dataPtr = pngData;
@@ -219,6 +230,7 @@ void ImageCairo::loadFromPng(const char* const pngData, const uint pngSize) noex
     cairo_surface_t* surface = cairo_image_surface_create_from_png_stream(&readSomePngData, &readerData);
     cairo_surface_destroy(fSurface);
     fSurface = surface;
+    fGc = gc;
 
     fRawData = (const char*)cairo_image_surface_get_data(surface);
     fSize.setWidth(cairo_image_surface_get_width(surface));
@@ -270,7 +282,7 @@ Image ImageCairo::getRegion(uint x, uint y, uint width, uint height) const noexc
     const uint stride = cairo_image_surface_get_stride(surface);
 
     unsigned char* data = fullData + x * bpp + y * stride;
-    return Image(cairo_image_surface_create_for_data(data, format, width, height, stride), false);
+    return Image(cairo_image_surface_create_for_data(data, format, width, height, stride), false, fGc);
 }
 
 cairo_surface_t* ImageCairo::getSurface() const noexcept
@@ -293,6 +305,7 @@ ImageCairo& ImageCairo::operator=(const ImageCairo& image) noexcept
     cairo_surface_t* surface = cairo_surface_reference(image.fSurface);
     cairo_surface_destroy(fSurface);
     fSurface = surface;
+    fGc = image.fGc;
 
     fRawData = (const char*)cairo_image_surface_get_data(surface);
     fSize.setWidth(cairo_image_surface_get_width(surface));
@@ -300,9 +313,12 @@ ImageCairo& ImageCairo::operator=(const ImageCairo& image) noexcept
     return *this;
 }
 
-void ImageCairo::_drawAt(const Point<int>& pos, const GraphicsContext& gc)
+void ImageCairo::_drawAt(const Point<int>& pos)
 {
-    cairo_t* cr = gc.cairo;
+    const GraphicsContext* gc = fGc;
+    DISTRHO_SAFE_ASSERT_RETURN(gc,)
+
+    cairo_t* cr = gc->cairo;
     cairo_surface_t* surface = fSurface;
 
     if (!fSurface)

dgl/src/ImageBase.cpp

@@ -67,40 +67,20 @@ const char* ImageBase::getRawData() const noexcept
 
 // -----------------------------------------------------------------------
 
-void ImageBase::draw(const GraphicsContext& gc)
-{
-    _drawAt(Point<int>(), gc);
-}
-
-void ImageBase::drawAt(const int x, const int y, const GraphicsContext& gc)
-{
-    _drawAt(Point<int>(x, y), gc);
-}
-
-void ImageBase::drawAt(const Point<int>& pos, const GraphicsContext& gc)
-{
-    _drawAt(pos, gc);
-}
-
-#ifdef DGL_OPENGL
 void ImageBase::draw()
 {
-    GraphicsContext gc;
-    _drawAt(Point<int>(), gc);
+    _drawAt(Point<int>());
 }
 
 void ImageBase::drawAt(const int x, const int y)
 {
-    GraphicsContext gc;
-    _drawAt(Point<int>(x, y), gc);
+    _drawAt(Point<int>(x, y));
 }
 
 void ImageBase::drawAt(const Point<int>& pos)
 {
-    GraphicsContext gc;
-    _drawAt(pos, gc);
+    _drawAt(pos);
 }
-#endif
 
 // -----------------------------------------------------------------------
 

dgl/src/ImageWidgets.cpp

@@ -61,9 +61,7 @@ void ImageAboutWindow::setImage(const Image& image)
 
 void ImageAboutWindow::onDisplay()
 {
-    const GraphicsContext& gc = getParentWindow().getGraphicsContext();
-
-    fImgBackground.draw(gc);
+    fImgBackground.draw();
 }
 
 bool ImageAboutWindow::onKeyboard(const KeyboardEvent& ev)
@@ -175,18 +173,16 @@ void ImageButton::setCallback(Callback* callback) noexcept
 
 void ImageButton::onDisplay()
 {
-    const GraphicsContext& gc = getParentWindow().getGraphicsContext();
-
     switch (pData->impl.state)
     {
     case ButtonImpl::kStateDown:
-        pData->imageDown.draw(gc);
+        pData->imageDown.draw();
         break;
     case ButtonImpl::kStateHover:
-        pData->imageHover.draw(gc);
+        pData->imageHover.draw();
         break;
     default:
-        pData->imageNormal.draw(gc);
+        pData->imageNormal.draw();
         break;
     }
 }
@@ -539,6 +535,7 @@ void ImageKnob::onDisplay()
 #ifdef DGL_CAIRO
 void ImageKnob::onDisplay()
 {
+    const GraphicsContext& gc = getParentWindow().getGraphicsContext();
     Image& displayImage = fDisplayImage;
     const int angle = fRotationAngle;
     const float normValue = ((fUsingLog ? _invlogscale(fValue) : fValue) - fMinimum) / (fMaximum - fMinimum);
@@ -559,7 +556,7 @@ void ImageKnob::onDisplay()
 
         if (angle != 0)
         {
-            Image rotated(cairo_image_surface_create(CAIRO_FORMAT_ARGB32, layerW, layerH), false);
+            Image rotated(cairo_image_surface_create(CAIRO_FORMAT_ARGB32, layerW, layerH), false, &gc);
             cairo_t* cr = cairo_create(rotated.getSurface());
             cairo_translate(cr, 0.5 * layerW, 0.5 * layerH);
             cairo_rotate(cr, normValue * angle * (float)(M_PI / 180));
@@ -572,8 +569,7 @@ void ImageKnob::onDisplay()
         fIsReady = true;
     }
 
-    const GraphicsContext& gc = getParentWindow().getGraphicsContext();
-    displayImage.draw(gc);
+    displayImage.draw();
 }
 #endif // DGL_CAIRO
 
@@ -873,8 +869,6 @@ void ImageSlider::setCallback(Callback* callback) noexcept
 
 void ImageSlider::onDisplay()
 {
-    const GraphicsContext& gc = getParentWindow().getGraphicsContext();
-
 #if 0 // DEBUG, paints slider area
     glColor3f(0.4f, 0.5f, 0.1f);
     glRecti(fSliderArea.getX(), fSliderArea.getY(), fSliderArea.getX()+fSliderArea.getWidth(), fSliderArea.getY()+fSliderArea.getHeight());
@@ -906,7 +900,7 @@ void ImageSlider::onDisplay()
             y = fStartPos.getY() + static_cast<int>(normValue*static_cast<float>(fEndPos.getY()-fStartPos.getY()));
     }
 
-    fImage.drawAt(x, y, gc);
+    fImage.drawAt(x, y);
 }
 
 bool ImageSlider::onMouse(const MouseEvent& ev)
@@ -1145,12 +1139,10 @@ void ImageSwitch::setCallback(Callback* callback) noexcept
 
 void ImageSwitch::onDisplay()
 {
-    const GraphicsContext& gc = getParentWindow().getGraphicsContext();
-
     if (fIsDown)
-        fImageDown.draw(gc);
+        fImageDown.draw();
     else
-        fImageNormal.draw(gc);
+        fImageNormal.draw();
 }
 
 bool ImageSwitch::onMouse(const MouseEvent& ev)

examples/CairoUI/CairoExampleUI.cpp

@@ -29,6 +29,8 @@ public:
     CairoExampleUI()
         : UI(200, 200)
     {
+        const GraphicsContext& gc = getParentWindow().getGraphicsContext();
+
         DemoWidgetClickable* widgetClickable = new DemoWidgetClickable(this);
         fWidgetClickable = widgetClickable;
         widgetClickable->setSize(50, 50);
@@ -40,7 +42,7 @@ public:
         widgetBanner->setAbsolutePos(10, 10);
 
         Image knobSkin;
-        knobSkin.loadFromPng(Artwork::knobData, Artwork::knobDataSize);
+        knobSkin.loadFromPng(Artwork::knobData, Artwork::knobDataSize, &gc);
 
         ImageKnob* knob = new ImageKnob(this, knobSkin);
         fKnob = knob;
@@ -49,8 +51,8 @@ public:
         // knob->setRotationAngle(270);
 
         Image buttonOn, buttonOff;
-        buttonOn.loadFromPng(Artwork::buttonOnData, Artwork::buttonOnDataSize);
-        buttonOff.loadFromPng(Artwork::buttonOffData, Artwork::buttonOffDataSize);
+        buttonOn.loadFromPng(Artwork::buttonOnData, Artwork::buttonOnDataSize, &gc);
+        buttonOff.loadFromPng(Artwork::buttonOffData, Artwork::buttonOffDataSize, &gc);
 
         ImageButton* button = new ImageButton(this, buttonOff, buttonOn);
         fButton = button;