FS#10 - Add rotation to sf::View

Slightly changed the public interface of sf::View

git-svn-id: https://sfml.svn.sourceforge.net/svnroot/sfml/branches/sfml2@1152 4e206d99-4929-0410-ac5d-dfc041789085

include/SFML/Graphics/Matrix3.hpp

@@ -72,10 +72,12 @@ public :
     ////////////////////////////////////////////////////////////
     /// Build a matrix from a projection
     ///
-    /// \param Rectangle : Rectangle defining the region to project
+    /// \param Center :   Center of the view
+    /// \param Size :     Size of the view
+    /// \param Rotation : Angle of rotation of the view rectangle, in degrees
     ///
     ////////////////////////////////////////////////////////////
-    void SetFromProjection(const FloatRect& Rectangle);
+    void SetFromProjection(const Vector2f& Center, const Vector2f& Size, float Rotation);
 
     ////////////////////////////////////////////////////////////
     /// Transform a point by the matrix

include/SFML/Graphics/Matrix3.inl

@@ -76,17 +76,24 @@ inline void Matrix3::SetFromTransformations(const Vector2f& Center, const Vector
 ////////////////////////////////////////////////////////////
 /// Build a matrix from a projection
 ////////////////////////////////////////////////////////////
-inline void Matrix3::SetFromProjection(const FloatRect& Rectangle)
+inline void Matrix3::SetFromProjection(const Vector2f& Center, const Vector2f& Size, float Rotation)
 {
+    // Rotation components
+    float Angle = Rotation * 3.141592654f / 180.f;
+    float Cos   = static_cast<float>(cos(Angle));
+    float Sin   = static_cast<float>(sin(Angle));
+    float Tx    = -Center.x * Cos - Center.y * Sin + Center.x;
+    float Ty    =  Center.x * Sin - Center.y * Cos + Center.y;
+
     // Projection components
-    float A =  2.f / Rectangle.GetSize().x;
+    float A =  2.f / Size.x;
-    float B = -2.f / Rectangle.GetSize().y;
+    float B = -2.f / Size.y;
-    float C = -(Rectangle.Left + Rectangle.Right) / Rectangle.GetSize().x;
+    float C = -A * Center.x;
-    float D =  (Rectangle.Bottom + Rectangle.Top) / Rectangle.GetSize().y;
+    float D = -B * Center.y;
 
     // Rebuild the projection matrix
-    myData[0] = A;   myData[4] = 0.f; myData[8]  = 0.f; myData[12] = C;
+    myData[0] =  A * Cos; myData[4] = A * Sin; myData[8]  = 0.f; myData[12] = A * Tx + C;
-    myData[1] = 0.f; myData[5] = B;   myData[9]  = 0.f; myData[13] = D;
+    myData[1] = -B * Sin; myData[5] = B * Cos; myData[9]  = 0.f; myData[13] = B * Ty + D;
     myData[2] = 0.f;      myData[6] = 0.f;     myData[10] = 1.f; myData[14] = 0.f;
     myData[3] = 0.f;      myData[7] = 0.f;     myData[11] = 0.f; myData[15] = 1.f;
 }

include/SFML/Graphics/View.hpp

@@ -37,20 +37,33 @@
 namespace sf
 {
 ////////////////////////////////////////////////////////////
-/// This class defines a view (position, size, etc.);
+/// This class defines a 2D view. A view is like a camera,
-/// you can consider it as a 2D camera
+/// which defines what part of the scene is shown and
+/// where it is shown.
+/// A sf::View is defined by the following components:
+/// its source rectangle in the scene, an optional rotation
+/// to apply to the source rectangle, and the destination
+/// rectangle where it will be displayed, in the render target
+/// that it is attached to.
 ////////////////////////////////////////////////////////////
 class SFML_API View
 {
 public :
 
     ////////////////////////////////////////////////////////////
-    /// Construct the view from a rectangle
+    /// Default constructor
-    ///
+    /// Constructs a default view of (0, 0, 1000, 1000)
-    /// \param ViewRect : Rectangle defining the position and size of the view (1000x1000 by default)
     ///
     ////////////////////////////////////////////////////////////
-    explicit View(const FloatRect& ViewRect = FloatRect(0, 0, 1000, 1000));
+    View();
+
+    ////////////////////////////////////////////////////////////
+    /// Construct the view from a rectangle
+    ///
+    /// \param Rectangle : Rectangle defining the view
+    ///
+    ////////////////////////////////////////////////////////////
+    explicit View(const FloatRect& Rectangle);
 
     ////////////////////////////////////////////////////////////
     /// Construct the view from its center and size
@@ -62,24 +75,7 @@ public :
     View(const Vector2f& Center, const Vector2f& Size);
 
     ////////////////////////////////////////////////////////////
-    /// Set the rectangle defining the view by its center and size
+    /// Change the center of the view
-    ///
-    /// \param Center : Center of the view rectangle
-    /// \param Size :   Size of the view rectangle
-    ///
-    ////////////////////////////////////////////////////////////
-    void SetRect(const Vector2f& Center, const Vector2f& Size);
-
-    ////////////////////////////////////////////////////////////
-    /// Set the rectangle defining the view
-    ///
-    /// \param Rect : Rectangle defining the center and size of the view
-    ///
-    ////////////////////////////////////////////////////////////
-    void SetRect(const FloatRect& Rect);
-
-    ////////////////////////////////////////////////////////////
-    /// Change the center of the view (take 2 values)
     ///
     /// \param X : X coordinate of the new center
     /// \param Y : Y coordinate of the new center
@@ -88,7 +84,7 @@ public :
     void SetCenter(float X, float Y);
 
     ////////////////////////////////////////////////////////////
-    /// Change the center of the view (take a vector)
+    /// Change the center of the view
     ///
     /// \param Center : New center
     ///
@@ -96,7 +92,7 @@ public :
     void SetCenter(const Vector2f& Center);
 
     ////////////////////////////////////////////////////////////
-    /// Change the size of the view (take 2 values)
+    /// Change the size of the view
     ///
     /// \param Width :  New width
     /// \param Height : New height
@@ -105,7 +101,7 @@ public :
     void SetSize(float Width, float Height);
 
     ////////////////////////////////////////////////////////////
-    /// Change the size of the view (take a vector)
+    /// Change the size of the view
     ///
     /// \param HalfSize : New half-size
     ///
@@ -113,13 +109,21 @@ public :
     void SetSize(const Vector2f& Size);
 
     ////////////////////////////////////////////////////////////
-    /// Get the rectangle defining the view,
+    /// Set the angle of rotation of the view
-    /// which is the combined center and size.
     ///
-    /// \return View rectangle
+    /// \param Angle : New angle, in degrees
     ///
     ////////////////////////////////////////////////////////////
-    FloatRect GetRect() const;
+    void SetRotation(float Angle);
+
+    ////////////////////////////////////////////////////////////
+    /// Reset the view to the given rectangle.
+    /// Note: this function resets the rotation angle to 0.
+    ///
+    /// \param Rectangle : Rectangle defining the view
+    ///
+    ////////////////////////////////////////////////////////////
+    void Reset(const FloatRect& Rectangle);
 
     ////////////////////////////////////////////////////////////
     /// Get the center of the view
@@ -138,7 +142,7 @@ public :
     const Vector2f& GetSize() const;
 
     ////////////////////////////////////////////////////////////
-    /// Move the view (take 2 values)
+    /// Move the view
     ///
     /// \param OffsetX : Offset to move the view, on X axis
     /// \param OffsetY : Offset to move the view, on Y axis
@@ -147,17 +151,25 @@ public :
     void Move(float OffsetX, float OffsetY);
 
     ////////////////////////////////////////////////////////////
-    /// Move the view (take a vector)
+    /// Move the view
     ///
     /// \param Offset : Offset to move the view
     ///
     ////////////////////////////////////////////////////////////
     void Move(const Vector2f& Offset);
 
+    ////////////////////////////////////////////////////////////
+    /// Rotate the view
+    ///
+    /// \param Angle : Angle to rotate, in degrees
+    ///
+    ////////////////////////////////////////////////////////////
+    void Rotate(float Angle);
+
     ////////////////////////////////////////////////////////////
     /// Resize the view rectangle to simulate a zoom / unzoom effect
     ///
-    /// \param Factor : Zoom factor to apply, relative to the current zoom
+    /// \param Factor : Zoom factor to apply, relative to the current size
     ///
     ////////////////////////////////////////////////////////////
     void Zoom(float Factor);
@@ -183,8 +195,9 @@ private :
     ////////////////////////////////////////////////////////////
     // Member data
     ////////////////////////////////////////////////////////////
-    sf::Vector2f    myCenter;        ///< Center of the view
+    Vector2f        myCenter;        ///< Center of the view, in scene coordinates
-    sf::Vector2f    mySize;          ///< Size of the view
+    Vector2f        mySize;          ///< Size of the view, in scene coordinates
+    float           myRotation;      ///< Angle of rotation of the view rectangle, in degrees
     mutable Matrix3 myMatrix;        ///< Precomputed projection matrix corresponding to the view
     mutable Matrix3 myInverseMatrix; ///< Precomputed inverse projection matrix corresponding to the view
     mutable bool    myNeedUpdate;    ///< Internal state telling if the matrix needs to be updated

samples/qt/Main.cpp

@@ -60,7 +60,7 @@ private :
             // Adjust the size of the default view when the widget is resized
             if (Event.Type == sf::Event::Resized)
             {
-                GetDefaultView().SetRect(sf::FloatRect(0, 0, Event.Size.Width, Event.Size.Height));
+                GetDefaultView().Reset(sf::FloatRect(0, 0, Event.Size.Width, Event.Size.Height));
             }
         }
 

src/SFML/Graphics/PostFX.cpp

@@ -303,13 +303,16 @@ void PostFX::Render(RenderTarget& Target) const
     IntRect FrameBufferRect(0, 0, myFrameBuffer.GetWidth(), myFrameBuffer.GetHeight());
     FloatRect TexCoords = myFrameBuffer.GetTexCoords(FrameBufferRect);
 
+    // Set the projection matrix to the identity so that the screen coordinates are in the range [-1, 1]
+    GLCheck(glMatrixMode(GL_PROJECTION));
+    GLCheck(glLoadIdentity());
+
     // Render a fullscreen quad using the effect on our framebuffer
-    FloatRect Screen = Target.GetView().GetRect();
     glBegin(GL_QUADS);
-         glTexCoord2f(TexCoords.Left,  TexCoords.Top);    glVertex2f(Screen.Left,  Screen.Top);
+         glTexCoord2f(TexCoords.Left,  TexCoords.Top);    glVertex2f(-1,  1);
-         glTexCoord2f(TexCoords.Right, TexCoords.Top);    glVertex2f(Screen.Right, Screen.Top);
+         glTexCoord2f(TexCoords.Right, TexCoords.Top);    glVertex2f( 1,  1);
-         glTexCoord2f(TexCoords.Right, TexCoords.Bottom); glVertex2f(Screen.Right, Screen.Bottom);
+         glTexCoord2f(TexCoords.Right, TexCoords.Bottom); glVertex2f( 1, -1);
-         glTexCoord2f(TexCoords.Left,  TexCoords.Bottom); glVertex2f(Screen.Left,  Screen.Bottom);
+         glTexCoord2f(TexCoords.Left,  TexCoords.Bottom); glVertex2f(-1, -1);
     glEnd();
 
     // Disable program

src/SFML/Graphics/RenderTarget.cpp

@@ -175,7 +175,7 @@ void RenderTarget::Initialize()
         SetRenderStates();
 
         // Setup the default view
-        myDefaultView.SetRect(FloatRect(0, 0, static_cast<float>(GetWidth()), static_cast<float>(GetHeight())));
+        myDefaultView.Reset(FloatRect(0, 0, static_cast<float>(GetWidth()), static_cast<float>(GetHeight())));
         SetView(myDefaultView);
 
         Activate(false);

src/SFML/Graphics/View.cpp

@@ -30,12 +30,32 @@
 
 namespace sf
 {
+////////////////////////////////////////////////////////////
+/// Default constructor
+/// Constructs a default view of (0, 0, 1000, 1000)
+////////////////////////////////////////////////////////////
+View::View() :
+myCenter       (),
+mySize         (),
+myRotation     (0),
+myNeedUpdate   (true),
+myNeedInvUpdate(true)
+{
+    Reset(FloatRect(0, 0, 1000, 1000));
+}
+
+
 ////////////////////////////////////////////////////////////
 /// Construct the view from a rectangle
 ////////////////////////////////////////////////////////////
-View::View(const FloatRect& Rect)
+View::View(const FloatRect& Rectangle) :
+myCenter       (),
+mySize         (),
+myRotation     (0),
+myNeedUpdate   (true),
+myNeedInvUpdate(true)
 {
-    SetRect(Rect);
+    Reset(Rectangle);
 }
 
 
@@ -45,36 +65,15 @@ View::View(const FloatRect& Rect)
 View::View(const Vector2f& Center, const Vector2f& Size) :
 myCenter       (Center),
 mySize         (Size),
+myRotation     (0),
 myNeedUpdate   (true),
 myNeedInvUpdate(true)
 {
 
 }
 
-
 ////////////////////////////////////////////////////////////
-/// Set the rectangle defining the view by its center and size
+/// Change the center of the view
-////////////////////////////////////////////////////////////
-void View::SetRect(const Vector2f& Center, const Vector2f& Size)
-{
-    myCenter        = Center;
-    mySize          = Size;
-    myNeedUpdate    = true;
-    myNeedInvUpdate = true;
-}
-
-
-////////////////////////////////////////////////////////////
-/// Set the rectangle defining the view
-////////////////////////////////////////////////////////////
-void View::SetRect(const FloatRect& Rect)
-{
-    SetRect(Rect.GetCenter(), Rect.GetSize());
-}
-
-
-////////////////////////////////////////////////////////////
-/// Change the center of the view (take 2 values)
 ////////////////////////////////////////////////////////////
 void View::SetCenter(float X, float Y)
 {
@@ -86,7 +85,7 @@ void View::SetCenter(float X, float Y)
 
 
 ////////////////////////////////////////////////////////////
-/// Change the center of the view (take a vector)
+/// Change the center of the view
 ////////////////////////////////////////////////////////////
 void View::SetCenter(const Vector2f& Center)
 {
@@ -95,7 +94,7 @@ void View::SetCenter(const Vector2f& Center)
 
 
 ////////////////////////////////////////////////////////////
-/// Change the size of the view (take 2 values)
+/// Change the size of the view
 ////////////////////////////////////////////////////////////
 void View::SetSize(float Width, float Height)
 {
@@ -107,7 +106,7 @@ void View::SetSize(float Width, float Height)
 
 
 ////////////////////////////////////////////////////////////
-/// Change the size of the view (take a vector)
+/// Change the size of the view
 ////////////////////////////////////////////////////////////
 void View::SetSize(const Vector2f& Size)
 {
@@ -116,15 +115,25 @@ void View::SetSize(const Vector2f& Size)
 
 
 ////////////////////////////////////////////////////////////
-/// Get the rectangle defining the view,
+/// Set the angle of rotation of the view
-/// which is the combined center and size.
 ////////////////////////////////////////////////////////////
-FloatRect View::GetRect() const
+void View::SetRotation(float Angle)
 {
-    return FloatRect(myCenter.x - mySize.x / 2,
+    myRotation      = Angle;
-                     myCenter.y - mySize.y / 2,
+    myNeedUpdate    = true;
-                     myCenter.x + mySize.x / 2,
+    myNeedInvUpdate = true;
-                     myCenter.y + mySize.y / 2);
+}
+
+
+////////////////////////////////////////////////////////////
+/// Reset the view to the given rectangle
+////////////////////////////////////////////////////////////
+void View::Reset(const FloatRect& Rectangle)
+{
+    myCenter        = Rectangle.GetCenter();
+    mySize          = Rectangle.GetSize();
+    myNeedUpdate    = true;
+    myNeedInvUpdate = true;
 }
 
 
@@ -147,7 +156,7 @@ const Vector2f& View::GetSize() const
 
 
 ////////////////////////////////////////////////////////////
-/// Move the view (take 2 values)
+/// Move the view
 ////////////////////////////////////////////////////////////
 void View::Move(float OffsetX, float OffsetY)
 {
@@ -159,7 +168,7 @@ void View::Move(float OffsetX, float OffsetY)
 
 
 ////////////////////////////////////////////////////////////
-/// Move the view (take a vector)
+/// Move the view
 ////////////////////////////////////////////////////////////
 void View::Move(const Vector2f& Offset)
 {
@@ -167,18 +176,27 @@ void View::Move(const Vector2f& Offset)
 }
 
 
+////////////////////////////////////////////////////////////
+/// Rotate the view
+////////////////////////////////////////////////////////////
+void View::Rotate(float Angle)
+{
+    myRotation     += Angle;
+    myNeedUpdate    = true;
+    myNeedInvUpdate = true;
+}
+
+
 ////////////////////////////////////////////////////////////
 /// Resize the view rectangle to simulate a zoom / unzoom effect
 ////////////////////////////////////////////////////////////
 void View::Zoom(float Factor)
 {
-    if (Factor != 0)
+    mySize.x       *= Factor;
-    {
+    mySize.y       *= Factor;
-        mySize /= Factor;
     myNeedUpdate    = true;
     myNeedInvUpdate = true;
 }
-}
 
 
 ////////////////////////////////////////////////////////////
@@ -189,7 +207,7 @@ const Matrix3& View::GetMatrix() const
     // Recompute the matrix if needed
     if (myNeedUpdate)
     {
-        myMatrix.SetFromProjection(GetRect());
+        myMatrix.SetFromProjection(myCenter, mySize, myRotation);
         myNeedUpdate = false;
     }