added orthographic projection

openglcanvas.cpp

@@ -522,6 +522,15 @@ void OpenGLCanvas::vertex_transformation(float *positions, int m, int n, float c
                 positions[3*(j+i*n)+1] = v/extent;
                 positions[3*(j+i*n)+2] = z;
             }
+
+            if (visualization=="Orthographic"){
+                u = x;
+                v = y;
+                positions[3*(j+i*n)] = u/extent;
+                positions[3*(j+i*n)+1] = v/extent;
+                positions[3*(j+i*n)+2] = z;
+            }
+
         }
     }
 
@@ -598,6 +607,14 @@ float OpenGLCanvas::calculate_extent(float fov_rads){
         u = x/(-z);
         v = y/(-z);
     }
+    if (visualization=="Orthographic"){
+        if(z<0.){
+            u=x;
+            v=y;
+        }else{
+            u=v=1.f;
+        }
+    }
     return u;
 }
 
@@ -789,6 +806,7 @@ void OpenGLCanvas::paintGL(){
     else if (visualization=="Stereographic") vis_mode=4.0;
     else if (visualization=="Mercator") vis_mode=5.0;
     else if (visualization=="Zorin-Barr") vis_mode=6.0;
+    else if (visualization=="Orthographic") vis_mode=7.0;
     glMatrixMode(GL_PROJECTION);
     glLoadIdentity();
     glOrtho(0.0, 2.0/extent, 0.0, 2.0/scale, 0.0, -2.0/vis_mode);

panowindow1.ui

@@ -207,6 +207,11 @@
        <string>Zorin-Barr</string>
       </property>
      </item>
+     <item>
+      <property name="text">
+       <string>Orthographic</string>
+      </property>
+     </item>
     </widget>
    </item>
    <item row="12" column="1">

shaders/vertex_shader.vert

@@ -92,6 +92,11 @@ void main(void){
         v=zbrho*sin(zbalpha);
         gl_Position = vec4(u/extent,v/extent,z,1.0);
     }
+    else if (vis_mode==7.0){ // Orthographic
+        u=x;
+        v=y;
+        gl_Position = vec4(u/extent,v/extent,z,1.0);
+    }
 
 //    gl_Position = vec4(u/2.0,v/2.0,z,1.0);