BGE: support camera scale, can be negative.

Camera scale was previously ignored in the BGE.
It is now injected in the modelview matrix as a scale of the scene
coordinates in the camera local reference. This is equivalent to a zoom:
A scale of 2 multiplies the coordinates by 2 => only the points with
coordinates less then 0.5 before the scale will fall in the frustrum =>
equivalent to a zoom.

Anisotropic scale is supported (different scale in x, y, z)
Negative scale is also supported. As an odd number of negative scale flips the
normals of the objects, the OGL front face setting is also flipped to compensate.

A Y negative scale of -1 produces a vertical flip at OGL level.

7 files changed, 15 insertions, 7 deletions

diff --git a/source/gameengine/Ketsji/KX_Dome.cpp b/source/gameengine/Ketsji/KX_Dome.cpp
index 07bed647b29..2220430dba9 100644
--- a/source/gameengine/Ketsji/KX_Dome.cpp
+++ b/source/gameengine/Ketsji/KX_Dome.cpp
@@ -1601,7 +1601,7 @@ void KX_Dome::RotateCamera(KX_Camera* cam, int i)
 
 	MT_Transform camtrans(cam->GetWorldToCamera());
 	MT_Matrix4x4 viewmat(camtrans);
-	m_rasterizer->SetViewMatrix(viewmat, cam->NodeGetWorldOrientation(), cam->NodeGetWorldPosition(), cam->GetCameraData()->m_perspective);
+	m_rasterizer->SetViewMatrix(viewmat, cam->NodeGetWorldOrientation(), cam->NodeGetWorldPosition(), cam->NodeGetLocalScaling(), cam->GetCameraData()->m_perspective);
 	cam->SetModelviewMatrix(viewmat);
 
 	// restore the original orientation
@@ -2036,7 +2036,7 @@ void KX_Dome::RenderDomeFrame(KX_Scene* scene, KX_Camera* cam, int i)
 
 	MT_Transform camtrans(cam->GetWorldToCamera());
 	MT_Matrix4x4 viewmat(camtrans);
-	m_rasterizer->SetViewMatrix(viewmat, cam->NodeGetWorldOrientation(), cam->NodeGetWorldPosition(), 1.0);
+	m_rasterizer->SetViewMatrix(viewmat, cam->NodeGetWorldOrientation(), cam->NodeGetWorldPosition(), cam->NodeGetLocalScaling(), 1.0);
 	cam->SetModelviewMatrix(viewmat);
 
 	// restore the original orientation
diff --git a/source/gameengine/Ketsji/KX_KetsjiEngine.cpp b/source/gameengine/Ketsji/KX_KetsjiEngine.cpp
index c9b868d4ff6..0cdaa28d528 100644
--- a/source/gameengine/Ketsji/KX_KetsjiEngine.cpp
+++ b/source/gameengine/Ketsji/KX_KetsjiEngine.cpp
@@ -1203,7 +1203,7 @@ void KX_KetsjiEngine::RenderFrame(KX_Scene* scene, KX_Camera* cam)
 	MT_Transform camtrans(cam->GetWorldToCamera());
 	MT_Matrix4x4 viewmat(camtrans);
 	
-	m_rasterizer->SetViewMatrix(viewmat, cam->NodeGetWorldOrientation(), cam->NodeGetWorldPosition(), cam->GetCameraData()->m_perspective);
+	m_rasterizer->SetViewMatrix(viewmat, cam->NodeGetWorldOrientation(), cam->NodeGetWorldPosition(), cam->NodeGetLocalScaling(), cam->GetCameraData()->m_perspective);
 	cam->SetModelviewMatrix(viewmat);
 
 	// The following actually reschedules all vertices to be
diff --git a/source/gameengine/Rasterizer/RAS_IRasterizer.h b/source/gameengine/Rasterizer/RAS_IRasterizer.h
index 8f4a7ffa983..72242bb4b1b 100644
--- a/source/gameengine/Rasterizer/RAS_IRasterizer.h
+++ b/source/gameengine/Rasterizer/RAS_IRasterizer.h
@@ -295,7 +295,7 @@ public:
 	 * Sets the modelview matrix.
 	 */
 	virtual void SetViewMatrix(const MT_Matrix4x4 &mat, const MT_Matrix3x3 &ori,
-	                           const MT_Point3 &pos, bool perspective) = 0;
+	                           const MT_Point3 &pos, const MT_Vector3 &scale, bool perspective) = 0;
 
 	/**
 	 */
diff --git a/source/gameengine/Rasterizer/RAS_OpenGLRasterizer/RAS_OpenGLLight.cpp b/source/gameengine/Rasterizer/RAS_OpenGLRasterizer/RAS_OpenGLLight.cpp
index 4ac1c9c4ebb..6199b0042ac 100644
--- a/source/gameengine/Rasterizer/RAS_OpenGLRasterizer/RAS_OpenGLLight.cpp
+++ b/source/gameengine/Rasterizer/RAS_OpenGLRasterizer/RAS_OpenGLLight.cpp
@@ -222,7 +222,7 @@ void RAS_OpenGLLight::BindShadowBuffer(RAS_ICanvas *canvas, KX_Camera *cam, MT_T
 	RAS_IRasterizer::StereoMode stereomode = m_rasterizer->GetStereoMode();
 	m_rasterizer->SetStereoMode(RAS_IRasterizer::RAS_STEREO_NOSTEREO);
 	m_rasterizer->SetProjectionMatrix(projectionmat);
-	m_rasterizer->SetViewMatrix(modelviewmat, cam->NodeGetWorldOrientation(), cam->NodeGetWorldPosition(), cam->GetCameraData()->m_perspective);
+	m_rasterizer->SetViewMatrix(modelviewmat, cam->NodeGetWorldOrientation(), cam->NodeGetWorldPosition(), cam->NodeGetLocalScaling(), cam->GetCameraData()->m_perspective);
 	m_rasterizer->SetStereoMode(stereomode);
 }
 
diff --git a/source/gameengine/Rasterizer/RAS_OpenGLRasterizer/RAS_OpenGLRasterizer.cpp b/source/gameengine/Rasterizer/RAS_OpenGLRasterizer/RAS_OpenGLRasterizer.cpp
index bef36b52956..6dff495cbc7 100644
--- a/source/gameengine/Rasterizer/RAS_OpenGLRasterizer/RAS_OpenGLRasterizer.cpp
+++ b/source/gameengine/Rasterizer/RAS_OpenGLRasterizer/RAS_OpenGLRasterizer.cpp
@@ -91,6 +91,7 @@ RAS_OpenGLRasterizer::RAS_OpenGLRasterizer(RAS_ICanvas* canvas, int storage)
 	m_time(0.0),
 	m_campos(0.0f, 0.0f, 0.0f),
 	m_camortho(false),
+	m_camnegscale(false),
 	m_stereomode(RAS_STEREO_NOSTEREO),
 	m_curreye(RAS_STEREO_LEFTEYE),
 	m_eyeseparation(0.0),
@@ -866,6 +867,7 @@ MT_Matrix4x4 RAS_OpenGLRasterizer::GetOrthoMatrix(
 void RAS_OpenGLRasterizer::SetViewMatrix(const MT_Matrix4x4 &mat, 
 										 const MT_Matrix3x3 & camOrientMat3x3,
 										 const MT_Point3 & pos,
+										 const MT_Vector3 &scale,
 										 bool perspective)
 {
 	m_viewmatrix = mat;
@@ -908,6 +910,7 @@ void RAS_OpenGLRasterizer::SetViewMatrix(const MT_Matrix4x4 &mat,
 		}
 	}
 
+	m_viewmatrix.tscale(scale[0], scale[1], scale[2], 1.0);
 	m_viewinvmatrix = m_viewmatrix;
 	m_viewinvmatrix.invert();
 
@@ -918,6 +921,7 @@ void RAS_OpenGLRasterizer::SetViewMatrix(const MT_Matrix4x4 &mat,
 	glMatrixMode(GL_MODELVIEW);
 	glLoadMatrixd(glviewmat);
 	m_campos = pos;
+	m_camnegscale = ((scale[0] < 0.0) ^ (scale[1] < 0.0) ^ (scale[2] < 0.0)) ? true : false;
 }
 
 
@@ -1050,6 +1054,9 @@ void RAS_OpenGLRasterizer::SetAlphaBlend(int alphablend)
 
 void RAS_OpenGLRasterizer::SetFrontFace(bool ccw)
 {
+	if (m_camnegscale)
+		ccw = !ccw;
+
 	if (m_last_frontface == ccw)
 		return;
 
diff --git a/source/gameengine/Rasterizer/RAS_OpenGLRasterizer/RAS_OpenGLRasterizer.h b/source/gameengine/Rasterizer/RAS_OpenGLRasterizer/RAS_OpenGLRasterizer.h
index afaa87fcd37..55e67a8db3e 100644
--- a/source/gameengine/Rasterizer/RAS_OpenGLRasterizer/RAS_OpenGLRasterizer.h
+++ b/source/gameengine/Rasterizer/RAS_OpenGLRasterizer/RAS_OpenGLRasterizer.h
@@ -97,6 +97,7 @@ class RAS_OpenGLRasterizer : public RAS_IRasterizer
 	MT_Matrix4x4 m_viewinvmatrix;
 	MT_Point3 m_campos;
 	bool m_camortho;
+	bool m_camnegscale;
 
 	StereoMode m_stereomode;
 	StereoEye m_curreye;
@@ -191,7 +192,7 @@ public:
 
 	virtual void SetProjectionMatrix(MT_CmMatrix4x4 &mat);
 	virtual void SetProjectionMatrix(const MT_Matrix4x4 &mat);
-	virtual void SetViewMatrix(const MT_Matrix4x4 &mat, const MT_Matrix3x3 &ori, const MT_Point3 &pos, bool perspective);
+	virtual void SetViewMatrix(const MT_Matrix4x4 &mat, const MT_Matrix3x3 &ori, const MT_Point3 &pos, const MT_Vector3 &scale, bool perspective);
 
 	virtual const MT_Point3& GetCameraPosition();
 	virtual bool GetCameraOrtho();
diff --git a/source/gameengine/VideoTexture/ImageRender.cpp b/source/gameengine/VideoTexture/ImageRender.cpp
index c4b3722fa8c..9db9a1a5f85 100644
--- a/source/gameengine/VideoTexture/ImageRender.cpp
+++ b/source/gameengine/VideoTexture/ImageRender.cpp
@@ -330,7 +330,7 @@ bool ImageRender::Render()
 	MT_Transform camtrans(m_camera->GetWorldToCamera());
 	MT_Matrix4x4 viewmat(camtrans);
 	
-	m_rasterizer->SetViewMatrix(viewmat, m_camera->NodeGetWorldOrientation(), m_camera->NodeGetWorldPosition(), m_camera->GetCameraData()->m_perspective);
+	m_rasterizer->SetViewMatrix(viewmat, m_camera->NodeGetWorldOrientation(), m_camera->NodeGetWorldPosition(), m_camera->NodeGetLocalScaling(), m_camera->GetCameraData()->m_perspective);
 	m_camera->SetModelviewMatrix(viewmat);
 	// restore the stereo mode now that the matrix is computed
 	m_rasterizer->SetStereoMode(stereomode);