Package ch.bailu.gtk.gdk

Class DrawContext

java.lang.Object
ch.bailu.gtk.type.Type
ch.bailu.gtk.type.Pointer
ch.bailu.gtk.gobject.Object
ch.bailu.gtk.gdk.DrawContext
All Implemented Interfaces:
PointerInterface
Direct Known Subclasses:
CairoContext, GLContext, VulkanContext
public class DrawContext extends Object
Base class for objects implementing different rendering methods.

`GdkDrawContext` is the base object used by contexts implementing different
rendering methods, such as [class@Gdk.CairoContext] or [class@Gdk.GLContext].
It provides shared functionality between those contexts.

You will always interact with one of those subclasses.

A `GdkDrawContext` is always associated with a single toplevel surface.

https://docs.gtk.org/gdk4/class.DrawContext.html

  • Constructor Details

  • Method Details

    • getClassHandler

      public static ClassHandler getClassHandler()

    • beginFrame

      public void beginFrame(@Nonnull Region region)
      Indicates that you are beginning the process of redrawing @region
      on the @context's surface.

      Calling this function begins a drawing operation using @context on the
      surface that @context was created from. The actual requirements and
      guarantees for the drawing operation vary for different implementations
      of drawing, so a [class@Gdk.CairoContext] and a [class@Gdk.GLContext]
      need to be treated differently.

      A call to this function is a requirement for drawing and must be
      followed by a call to [method@Gdk.DrawContext.end_frame], which will
      complete the drawing operation and ensure the contents become visible
      on screen.

      Note that the @region passed to this function is the minimum region that
      needs to be drawn and depending on implementation, windowing system and
      hardware in use, it might be necessary to draw a larger region. Drawing
      implementation must use [method@Gdk.DrawContext.get_frame_region] to
      query the region that must be drawn.

      When using GTK, the widget system automatically places calls to
      gdk_draw_context_begin_frame() and gdk_draw_context_end_frame() via the
      use of [class@Gsk.Renderer]s, so application code does not need to call
      these functions explicitly.
      Parameters:
      region - minimum region that should be drawn

    • endFrame

      public void endFrame()
      Ends a drawing operation started with gdk_draw_context_begin_frame().

      This makes the drawing available on screen.
      See [method@Gdk.DrawContext.begin_frame] for more details about drawing.

      When using a [class@Gdk.GLContext], this function may call `glFlush()`
      implicitly before returning; it is not recommended to call `glFlush()`
      explicitly before calling this function.

    • getDisplay

      public Display getDisplay()
      Retrieves the `GdkDisplay` the @context is created for
      Returns:
      the `GdkDisplay`

    • getFrameRegion

      public Region getFrameRegion()
      Retrieves the region that is currently being repainted.

      After a call to [method@Gdk.DrawContext.begin_frame] this function will
      return a union of the region passed to that function and the area of the
      surface that the @context determined needs to be repainted.

      If @context is not in between calls to [method@Gdk.DrawContext.begin_frame]
      and [method@Gdk.DrawContext.end_frame], %NULL will be returned.
      Returns:
      a Cairo region

    • getSurface

      public Surface getSurface()
      Retrieves the surface that @context is bound to.
      Returns:
      a `GdkSurface`

    • isInFrame

      public boolean isInFrame()
      Returns %TRUE if @context is in the process of drawing to its surface.

      This is the case between calls to [method@Gdk.DrawContext.begin_frame]
      and [method@Gdk.DrawContext.end_frame]. In this situation, drawing commands
      may be effecting the contents of the @context's surface.
      Returns:
      %TRUE if the context is between [method@Gdk.DrawContext.begin_frame] and [method@Gdk.DrawContext.end_frame] calls.

    • getTypeID

      public static long getTypeID()

    • getParentTypeID

      public static long getParentTypeID()

    • getTypeSize

      public static TypeSystem.TypeSize getTypeSize()

    • getParentTypeSize

      public static TypeSystem.TypeSize getParentTypeSize()

    • getInstanceSize

      public static int getInstanceSize()