Improve line rounding compensation

.idea/gradle.xml

@@ -15,6 +15,7 @@
           </set>
         </option>
         <option name="resolveModulePerSourceSet" value="false" />
+        <option name="useQualifiedModuleNames" value="true" />
       </GradleProjectSettings>
     </option>
   </component>

app/src/main/java/de/hems/trafficsim/Renderer.java

@@ -74,8 +74,10 @@ public class Renderer {
             synchronized (holder) {
                 int y = 0;
                 int left = 0;
-                int compensate = 0;
-                float vCompensate = 0;
+                int hCompensateStart = 0;
+                int hCompensateEnd = 0;
+                int vCompensateStart = 0;
+                int vCompensateEnd = 0;
                 canvas.drawColor(Color.BLACK);
                 for (int curStepIdx = this.track.getVtrList().size()-1;curStepIdx >= 0;
                      curStepIdx--) {
@@ -85,17 +87,18 @@ public class Renderer {
                         } catch (InterruptedException ex) {
                             return;
                         }
-                        vCompensate = Math.round(y * this.tooShortPerHeight);
+                        vCompensateStart = Math.round(y * this.tooShortPerHeight);
+                        vCompensateEnd = Math.round((y+this.pixelPerLine) * this.tooShortPerHeight);
                         stepRecords = this.track.getVtrList().get(curStepIdx);
                         int i = 0;
                         for (VehicleTimeRecord r : stepRecords) {
                             left = (int) (this.pixelPerVehicle * r.getPosition());
-                            compensate = Math.round(r.getPosition() * this.tooShortPerTrackLength);
-
+                            hCompensateStart = Math.round(r.getPosition() * this.tooShortPerTrackLength);
+                            hCompensateEnd = Math.round((r.getPosition() + this.pixelPerVehicle) * this.tooShortPerTrackLength);
                             this.paint.setColor(getColor(r.getVelocity(), r.getMaxVelocity()));
-                            canvas.drawRect(left + compensate, y+vCompensate,
-                                    left + this.pixelPerVehicle + compensate,
-                                    y + pixelPerLine + vCompensate, this.paint);
+                            canvas.drawRect(left + hCompensateStart, y+vCompensateStart,
+                                    left + this.pixelPerVehicle + hCompensateEnd,
+                                    y + pixelPerLine + vCompensateEnd, this.paint);
                             i++;
                         }
                         track.getListSemaphore().release();