Bug #589 uykusuz's improvements

git-svn-id: https://svn.code.sf.net/p/speed-dreams/code/trunk@4990 30fe4595-0a0c-4342-8851-515496e4dcbd

Former-commit-id: 1312882a481d7b6f83629e2a54651200be044823
Former-commit-id: 2da1347370384904b0db1312c21af9194179a2da

src/modules/graphic/ssggraph/grcam.cpp

@@ -48,6 +48,11 @@ cGrCamera::getDist2 (tCarElt *car)
     return dx * dx + dy * dy;
 }
 
+float
+cGrCamera::getAspectRatio()
+{
+    return screen->getViewRatio();
+}
 
 static void
 grMakeLookAtMat4 ( sgMat4 dst, const sgVec3 eye, const sgVec3 center, const sgVec3 up )
@@ -116,7 +121,7 @@ void cGrPerspCamera::setProjection(void)
     // tan and atan functions operate on angles in radians. Also,
     // we're only interested in half the viewing angle.
 
-    float fovx = atan(screen->getViewRatio() / spanaspect * tan(fovy * M_PI / 360.0)) * 360.0 / M_PI;
+    float fovx = atan(getAspectRatio() / spanaspect * tan(fovy * M_PI / 360.0)) * 360.0 / M_PI;
     grContext.setFOV(fovx, fovy);
     grContext.setNearFar(fnear, ffar);
 }
@@ -493,6 +498,7 @@ cGrCarCamMirror::cGrCarCamMirror(cGrScreen *myscreen, int id, int drawCurr, int
     : cGrPerspCamera(myscreen, id, drawCurr, 1, drawBG, 1,
          myfovy, myfovymin, myfovymax,
          myfnear, myffar, myfogstart, myfogend)
+    , origFovY(myfovy)
 {
 }
 
@@ -550,7 +556,6 @@ void cGrCarCamMirror::adaptScreenSize()
     vpy = screen->getScrY();
     vpw = screen->getScrW();
     vph = screen->getScrH();
-    vp_aspectratio = double(vph)/vpw;
 
     // mirror width adjusted to fit board size
     int boardW = screen->getBoardWidth();
@@ -559,35 +564,23 @@ void cGrCarCamMirror::adaptScreenSize()
     my = vpy +  5 * vph / 6 - vph / 10;
     mw = vpw * boardW /200;
     mh = vph / 6;
-    m_centery = my + mh/2;
+
+    aspectRatio = float(mw) / mh;
+
+    limitFov();
 }
 
 void cGrCarCamMirror::beforeDraw (void)
 {
     glFrontFace( GL_CW );
 
-    /* The aspect ratio of the mirror is probably not the same
-     * as the real aspect ratio. Thus we do the following:
-     * 1) set up the mirror viewport with the same aspect ratio
-     *   as the real scene
-     * 2) scissor the area of the actual mirror
-     *
-     * The viewport in 1) will be the same as the actual mirror,
-     * but with the height adjusted to fit the real aspect ratio.
-     * For that the mirror's height is calculated by multiplying
-     * the mirror's width with the real aspect ratio.
-     * To get the lower-left corner of the mirror's viewport half
-     * of that new height is subtracted from the mirror center's
-     * y-coordinate.
-     */
-
-    double mvph = mw * vp_aspectratio;
-    int mvpy = m_centery - (mvph/2);
-
-    glViewport(mx, mvpy, mw, mvph);
-
+    // Scissor needed with Nouveau driver
     glEnable(GL_SCISSOR_TEST);
     glScissor(mx, my, mw, mh);
+    glViewport(mx, my, mw, mh);
+
+    // make mirror in front of everything by forcing overdrawing of everything
+    glClear(GL_DEPTH_BUFFER_BIT);
 }
 
 void cGrCarCamMirror::afterDraw (void)
@@ -599,6 +592,11 @@ void cGrCarCamMirror::afterDraw (void)
     glFrontFace( GL_CCW );
 }
 
+void cGrCarCamMirror::limitFov(void)
+{
+    fovy = origFovY / getAspectRatio();
+}
+
 // cGrCarCamInsideFixedCar ================================================================
 
 class cGrCarCamInsideFixedCar : public cGrPerspCamera

src/modules/graphic/ssggraph/grcam.h

@@ -77,6 +77,14 @@ class cGrCamera
 
     virtual float getLODFactor(float x, float y, float z) = 0;	/* Get the LOD factor for an object located at x,y,z */
 
+    /** Retrieve the aspect ratio of this camera. This is used in
+     *  cGrPerspCamera::setProjection() to calculate the fov.
+     *  Usually this is simply the screen's aspect ratio. But for example the mirror's cam
+     *  has another aspect ratio, which needs to be taken into account when setting up the
+     *  view.
+     */
+    virtual float getAspectRatio();
+
     /* Set the camera view */
     void action(void) {
 	setProjection();
@@ -167,11 +175,11 @@ class cGrPerspCamera : public cGrCamera
 		   float myfnear, float myffar = 1500.0, float myfogstart = 1400.0, float myfogend = 1500.0);
     
     virtual void update(tCarElt *car, tSituation *s) = 0;	/* Change the camera if necessary */
-    void setProjection(void);
-    void setModelView(void);
-    void loadDefaults(char *attr);
+    virtual void setProjection(void);
+    virtual void setModelView(void);
+    virtual void loadDefaults(char *attr);
     void setViewOffset(float newOffset);
-    void setZoom(int cmd);
+    virtual void setZoom(int cmd);
     float getLODFactor(float x, float y, float z);
     float getFogStart(void) { return fogstart; }
     float getFogEnd(void) { return fogend; }
@@ -187,7 +195,7 @@ class cGrPerspCamera : public cGrCamera
 	return (cGrPerspCamera *)cGrCamera::next();
     }
 
-   void limitFov(void)  {}
+   virtual void limitFov(void)  {}
    void onSelect(tCarElt *car, tSituation *s) {}
 
    virtual float getFovY(void) {
@@ -221,7 +229,7 @@ class cGrOrthoCamera : public cGrCamera
     void update(tCarElt *car, tSituation *s) { }
     float getLODFactor(float x, float y, float z) { return 1; }
     void loadDefaults(char *attr) { }
-    void setZoom(int cmd) { }
+    virtual void setZoom(int cmd) { }
     void onSelect(tCarElt *car, tSituation *s) {}
 };
 
@@ -247,9 +255,9 @@ class cGrCarCamMirror : public cGrPerspCamera
 {
  protected:
     int		vpx, vpy, vpw, vph;	/* viewport size */
-    double  vp_aspectratio;     /* viewport aspect ratio: vph/vpw */
     int		mx, my, mw, mh;		/* drawing area */
-    int     m_centery;          /* y-coordinate of the mirror's center point */
+    float   aspectRatio;        /* the aspect ratio of the mirror: mw / mh */
+    float   origFovY;           /* fovy set using constructor */
     
  public:
     cGrCarCamMirror(cGrScreen *myscreen, int id, int drawCurr, int drawBG,
@@ -259,6 +267,8 @@ class cGrCarCamMirror : public cGrPerspCamera
 
     void update (tCarElt *car, tSituation *s);
 
+    virtual float getAspectRatio() { return aspectRatio; }
+
     void setViewport (int x, int y, int w, int h);
     void setScreenPos (int x, int y, int w, int h);
 
@@ -267,9 +277,12 @@ class cGrCarCamMirror : public cGrPerspCamera
     virtual void beforeDraw(void);
     virtual void afterDraw(void);
 
+
     /** Called by cGrScreen::activate() after the screen updated it's screen size.
      *  Cameras should use the cGrCamera::screen property to get the updated information. */
     void adaptScreenSize();
+
+    virtual void limitFov(void);
 };