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    • By Epicghost 505
      Hello,
      We are looking for people to be apart of a team, to help create a horror game we are looking for 3d modelers, coders, artist, animators, fx artist, level designers, and audio design, there will be a payment plan once release of game                                                                                                                                                                                                                                                                                              if your interested come join our discord                                                                                                                                                                                                                                                                         We hope to see you there
      https://discord.gg/6rcc6xr
      -Epicghost505
    • By ethancodes
      I'm having a weird issue with detecting a collision. I've tried everything I could find online but nothing seems to work. I have a brick object. It has a 2D Collider attached and I have also attached a 2D Rigidbody on it. I also have an EndScreen 2D Collider. The EndScreen 2D collider is tagged with "EndScreen". I am trying to detect when a brick collides with the end screen collider and simply print "game over" in the console. 
      This is my current code for this part of the program, it is attached to the bricks:
      void OnCollisionEnter (Collision2D collision) { if (collision.gameObject.tag == "EndScreen") { Debug.Log("Game over"); } } Several things have happened depending on the set up. If I have the rigidbody 2D set as static, my ball object can still collide with the bricks, but I get no Log message. If I set it to Kinematic or Dynamic, I get absolutely no interaction between the ball and the bricks, and nothing when the bricks pass through the collider. I have tried to set the collider to a trigger and use OnTriggerEnter2D, no change. I have tried to put the rigidbody on the EndScreen object and tried to set it's body type to all 3 settings, no change. The only thing I can think of that I have not done is put the script on the EndScreen object and switch the tag to the bricks. The reason I have not done this is because I will have several types of bricks, some of which will have different tags. 
       
      Please tell me somebody can see what I'm doing wrong here, because I'm losing my mind over something I feel should be ridiculously simple. Thanks.
    • By ethancodes
      I'm working on an endless wave-based arkanoid/space invaders style hybrid. Bricks spawn above the screen and move down line by line. You must destroy all bricks before they hit the bottom of the screen. There will be multiple types of bricks and random power-up spawns. Currently I am just using a simple Log function that takes in the current wave as a parameter. This works to increase the number of bricks spawned each wave, but I want to find a way to make this much more complicated. Here is a list of everything that should be effected by the increase in difficulty:
      1. Number of bricks
      2. Types of bricks (1 hit bricks, 2 hit bricks, 3 hit bricks, etc.) 
      3. Speed that the bricks move down the screen
      4. How often power-ups spawn
      The biggest problem here is that I can't just increase all of these with each new wave. If I did that, it would quickly become far to difficult. What I would like is an algorithm that gives some amount of variance in the increase between all 4 of these. Say one wave we put 60% of the increase to number of bricks, 20% increase to power-up spawns, 10% to types of bricks and 10% to speed of bricks. But on the next wave those percentages are all moved around and we now have say 105% to work with so the overall difficulty has increased as well. The different types of bricks need to also change to the point where if someone has made it to a certain wave, such as wave 50 for example, there are no longer any 1 hit bricks. We now would have just 2-4 hit bricks, and if they are crazy good and make it all the way to round 100, Now it's just 3-5 hit bricks, etc. 
      If anybody has any good ideas or suggestions on this, I'd appreciate anything you've got! Thanks!
    • By PVS-studio team
      Recently a long-awaited event has happen - Unity Technologies uploaded the C# source code of the game engine, available for free download on Github. The code of the engine and the editor is available. Of course, we couldn't pass up, especially since lately we've not written so many articles about checking projects on C#. Unity allows to use the provided sources only for information purposes. We'll use them exactly in these ways. Let's try out the latest version PVS-Studio 6.23 on the Unity code.

      Introduction
      Previously we've written an article about checking Unity. At that time so much C#-code was not available for the analysis: some components, libraries and examples of usage. However, the author of the article managed to find quite interesting bugs.
      How did Unity please us this time? I'm saying "please" and hope not to offend the authors of the project. Especially since the amount of the source Unity C#-code, presented on GitHub, is about 400 thousand lines (excluding empty) in 2058 files with the extension "cs". It's a lot, and the analyzer had a quite considerable scope.
      Now about the results. Before the analysis, I've slightly simplified the work, having enabled the mode of the code display according to the CWE classification for the found bugs. I've also activated the warnings suppression mechanism of the third level of certainty (Low). These settings are available in the drop-down menu of PVS-Studio in Visual Studio development environment, and in the parameters of the analyzer. Getting rid of the warnings with low certainty, I made the analysis of the Unity source code. As a result, I got 181 warnings of the first level of certainty (High) and 506 warnings of the second level of certainty (Medium).
      I have not studied absolutely all the warnings, because there were quite a lot of them. Developers or enthusiasts can easily conduct an in-depth analysis by testing Unity themselves. To do this, PVS-Studio provides free trial and free modes of using. Companies can also buy our product and get quick and detailed support along with the license.
      Judging by the fact that I immediately managed to find couple of real bugs practically in every group of warnings with one or two attempts, there are a lot of them in Unity. And yes, they are diverse. Let's review the most interesting errors.

      Results of the check
      Something's wrong with the flags
      PVS-Studio warning: V3001 There are identical sub-expressions 'MethodAttributes.Public' to the left and to the right of the '|' operator. SyncListStructProcessor.cs 240
      MethodReference GenerateSerialization() { .... MethodDefinition serializeFunc = new MethodDefinition("SerializeItem", MethodAttributes.Public | MethodAttributes.Virtual | MethodAttributes.Public | // <= MethodAttributes.HideBySig, Weaver.voidType); .... } When combining enumeration flags MethodAttributes, an error was made: the Public value was used twice. Perhaps, the reason for this is the wrong code formatting.
      A similar bug is also made in code of the method GenerateDeserialization:
      V3001 There are identical sub-expressions 'MethodAttributes.Public' to the left and to the right of the '|' operator. SyncListStructProcessor.cs 309 Copy-Paste
      PVS-Studio warning: V3001 There are identical sub-expressions 'format == RenderTextureFormat.ARGBFloat' to the left and to the right of the '||' operator. RenderTextureEditor.cs 87
      public static bool IsHDRFormat(RenderTextureFormat format) { Return (format == RenderTextureFormat.ARGBHalf || format == RenderTextureFormat.RGB111110Float || format == RenderTextureFormat.RGFloat || format == RenderTextureFormat.ARGBFloat || format == RenderTextureFormat.ARGBFloat || format == RenderTextureFormat.RFloat || format == RenderTextureFormat.RGHalf || format == RenderTextureFormat.RHalf); } I gave a piece of code, preliminary having formatted it, so the error is easily detected visually: the comparison with RenderTextureFormat.ARGBFloat is performed twice. In the original code, it looks differently:
      Probably, another value of enumeration RenderTextureFormat has to be used in one of two identical comparisons.
      Double work
      PVS-Studio warning: V3008 CWE-563 The 'fail' variable is assigned values twice successively. Perhaps this is a mistake. Check lines: 1633, 1632. UNetWeaver.cs 1633
      class Weaver { .... public static bool fail; .... static public bool IsValidTypeToGenerate(....) { .... if (....) { .... Weaver.fail = true; fail = true; return false; } return true; } .... } The true value is assigned twice to the value, as Weaver.fail and fail is one and the same static field of the Weaver class. Perhaps, there is no crucial error, but the code definitely needs attention.
      No options
      PVS-Studio warning: V3009 CWE-393 It's odd that this method always returns one and the same value of 'false'. ProjectBrowser.cs 1417
      // Returns true if we should early out of OnGUI bool HandleCommandEventsForTreeView() { .... if (....) { .... if (....) return false; .... } return false; } The method always returns false. Pay attention to the comment in the beginning.
      A developer forgot about the result
      PVS-Studio warning: V3010 CWE-252 The return value of function 'Concat' is required to be utilized. AnimationRecording.cs 455
      static public UndoPropertyModification[] Process(....) { .... discardedModifications.Concat(discardedRotationModifications); return discardedModifications.ToArray(); } When concatenating two arrays discardedModifications and discardedRotationModifications the author forgot to save the result. Probably a programmer assumed that the result would be expressed immediately in the array discardedModifications. But it is not so. As a result, the original array discardedModifications is returned from the method. The code needs to be corrected as follows:
      static public UndoPropertyModification[] Process(....) { .... return discardedModifications.Concat(discardedRotationModifications) .ToArray(); } Wrong variable was checked
      PVS-Studio warning: V3019 CWE-697 Possibly an incorrect variable is compared to null after type conversion using 'as' keyword. Check variables 'obj', 'newResolution'. GameViewSizesMenuItemProvider.cs 104
      private static GameViewSize CastToGameViewSize(object obj) { GameViewSize newResolution = obj as GameViewSize; if (obj == null) { Debug.LogError("Incorrect input"); return null; } return newResolution; } In this method, the developers forgot to consider a situation where the variable objis not equal to null, but it will not be able to cast to the GameViewSize type. Then the variable newResolution will be set to null, and the debug output will not be made. A correct variant of code will be like this:
      private static GameViewSize CastToGameViewSize(object obj) { GameViewSize newResolution = obj as GameViewSize; if (newResolution == null) { Debug.LogError("Incorrect input"); } return newResolution; } Deficiency
      PVS-Studio warning: V3020 CWE-670 An unconditional 'return' within a loop. PolygonCollider2DEditor.cs 96
      private void HandleDragAndDrop(Rect targetRect) { .... foreach (....) { .... if (....) { .... } return; } .... } The loop will execute only one iteration, after that the method terminates its work. Various scenarios are probable. For example, return must be inside the unit if, or somewhere before return, a directive continue is missing. It may well be that there is no error here, but then one should make the code more understandable.
      Unreachable code
      PVS-Studio warning: V3021 CWE-561 There are two 'if' statements with identical conditional expressions. The first 'if' statement contains method return. This means that the second 'if' statement is senseless CustomScriptAssembly.cs 179
      public bool IsCompatibleWith(....) { .... if (buildingForEditor) return IsCompatibleWithEditor(); if (buildingForEditor) buildTarget = BuildTarget.NoTarget; // Editor .... } Two identical checks, following one after another. It is clear that in case of buildingForEditor equality to the true value, the second check is meaningless, because the first method terminates its work. If the value buildingForEditor is false, neither then-brunch nor if operator will be executed. There is an erroneous construction that requires correction.
      Unconditional condition
      PVS-Studio warning: V3022 CWE-570 Expression 'index < 0 && index >= parameters.Length' is always false. AnimatorControllerPlayable.bindings.cs 287
      public AnimatorControllerParameter GetParameter(int index) { AnimatorControllerParameter[] param = parameters; if (index < 0 && index >= parameters.Length) throw new IndexOutOfRangeException( "Index must be between 0 and " + parameters.Length); return param[index]; } The condition of the index check is incorrect - the result will always be false. However, in case of passing the incorrect index to the GetParameter method, the exception IndexOutOfRangeException will still be thrown when attempting to access an array element in the return block. Although, the error message will be slightly different. One has to use || in a condition instead of the operator && so that the code worked the way a developer expected:
      public AnimatorControllerParameter GetParameter(int index) { AnimatorControllerParameter[] param = parameters; if (index < 0 || index >= parameters.Length) throw new IndexOutOfRangeException( "Index must be between 0 and " + parameters.Length); return param[index]; } Perhaps, due to the use of the Copy-Paste method, there is another the same error in the Unity code:
      PVS-Studio warning: V3022 CWE-570 Expression 'index < 0 && index >= parameters.Length' is always false. Animator.bindings.cs 711
      And another similar error associated with the incorrect condition of the check of the array index:
      PVS-Studio warning: V3022 CWE-570 Expression 'handle.valueIndex < 0 && handle.valueIndex >= list.Length' is always false. StyleSheet.cs 81
      static T CheckAccess<T>(T[] list, StyleValueType type, StyleValueHandle handle) { T value = default(T); if (handle.valueType != type) { Debug.LogErrorFormat(.... ); } else if (handle.valueIndex < 0 && handle.valueIndex >= list.Length) { Debug.LogError("Accessing invalid property"); } else { value = list[handle.valueIndex]; } return value; } And in this case, a release of the IndexOutOfRangeException exception is possible.As in the previous code fragments, one has to use the operator || instead of && to fix an error.
      Simply strange code
      Two warnings are issued for the code fragment below.
      PVS-Studio warning: V3022 CWE-571 Expression 'bRegisterAllDefinitions || (AudioSettings.GetSpatializerPluginName() == "GVR Audio Spatializer")' is always true. AudioExtensions.cs 463
      PVS-Studio warning: V3022 CWE-571 Expression 'bRegisterAllDefinitions || (AudioSettings.GetAmbisonicDecoderPluginName() == "GVR Audio Spatializer")' is always true. AudioExtensions.cs 467
      // This is where we register our built-in spatializer extensions. static private void RegisterBuiltinDefinitions() { bool bRegisterAllDefinitions = true; if (!m_BuiltinDefinitionsRegistered) { if (bRegisterAllDefinitions || (AudioSettings.GetSpatializerPluginName() == "GVR Audio Spatializer")) { } if (bRegisterAllDefinitions || (AudioSettings.GetAmbisonicDecoderPluginName() == "GVR Audio Spatializer")) { } m_BuiltinDefinitionsRegistered = true; } } It looks like an incomplete method. It is unclear why it has been left as such and why developers haven't commented the useless code blocks. All, that the method does at the moment:
      if (!m_BuiltinDefinitionsRegistered) { m_BuiltinDefinitionsRegistered = true; } Useless method
      PVS-Studio warning: V3022 CWE-570 Expression 'PerceptionRemotingPlugin.GetConnectionState() != HolographicStreamerConnectionState.Disconnected' is always false. HolographicEmulationWindow.cs 171
      private void Disconnect() { if (PerceptionRemotingPlugin.GetConnectionState() != HolographicStreamerConnectionState.Disconnected) PerceptionRemotingPlugin.Disconnect(); } To clarify the situation, it is necessary to look at the declaration of the methodPerceptionRemotingPlugin.GetConnectionState():
      internal static HolographicStreamerConnectionState GetConnectionState() { return HolographicStreamerConnectionState.Disconnected; } Thus, calling the Disconnect() method leads to nothing.
      One more error relates to the same method PerceptionRemotingPlugin.GetConnectionState():
      PVS-Studio warning: V3022 CWE-570 Expression 'PerceptionRemotingPlugin.GetConnectionState() == HolographicStreamerConnectionState.Connected' is always false. HolographicEmulationWindow.cs 177
      private bool IsConnectedToRemoteDevice() { return PerceptionRemotingPlugin.GetConnectionState() == HolographicStreamerConnectionState.Connected; } The result of the method is equivalent to the following:
      private bool IsConnectedToRemoteDevice() { return false; } As we can see, among the warnings V3022 many interesting ones were found. Probably, if one spends much time, he can increase the list. But let's move on.
      Not on the format
      PVS-Studio warning: V3025 CWE-685 Incorrect format. A different number of format items is expected while calling 'Format' function. Arguments not used: index. Physics2D.bindings.cs 2823
      public void SetPath(....) { if (index < 0) throw new ArgumentOutOfRangeException( String.Format("Negative path index is invalid.", index)); .... } There is no error in code, but as the saying goes, the code "smells". Probably, an earlier message was more informative, like this: "Negative path index {0} is invalid.". Then it was simplified, but developers forgot to remove the parameter index for the method Format. Of course, this is not the same as a forgotten parameter for the indicated output string specifier, i.e. the construction of the type String.Format("Negative path index {0} is invalid."). In such a case, an exception would be thrown. But in our case we also need neatness when refactoring. The code has to be fixed as follows:
      public void SetPath(....) { if (index < 0) throw new ArgumentOutOfRangeException( "Negative path index is invalid."); .... } Substring of the substring
      PVS-Studio warning: V3053 An excessive expression. Examine the substrings 'UnityEngine.' and 'UnityEngine.SetupCoroutine'. StackTrace.cs 43
      static bool IsSystemStacktraceType(object name) { string casted = (string)name; return casted.StartsWith("UnityEditor.") || casted.StartsWith("UnityEngine.") || casted.StartsWith("System.") || casted.StartsWith("UnityScript.Lang.") || casted.StartsWith("Boo.Lang.") || casted.StartsWith("UnityEngine.SetupCoroutine"); } Search of the substring "UnityEngine.SetupCoroutine" in the condition is meaningless, because before that the search for "UnityEngine." is performed. Therefore, the last check should be removed or one has to clarify the correctness of substrings.
      Another similar error:
      PVS-Studio warning: V3053 An excessive expression. Examine the substrings 'Windows.dll' and 'Windows.'. AssemblyHelper.cs 84
      static private bool CouldBelongToDotNetOrWindowsRuntime(string assemblyPath) { return assemblyPath.IndexOf("mscorlib.dll") != -1 || assemblyPath.IndexOf("System.") != -1 || assemblyPath.IndexOf("Windows.dll") != -1 || // <= assemblyPath.IndexOf("Microsoft.") != -1 || assemblyPath.IndexOf("Windows.") != -1 || // <= assemblyPath.IndexOf("WinRTLegacy.dll") != -1 || assemblyPath.IndexOf("platform.dll") != -1; } Size does matter
      PVS-Studio warning: V3063 CWE-571 A part of conditional expression is always true if it is evaluated: pageSize <= 1000. UNETInterface.cs 584
      public override bool IsValid() { .... return base.IsValid() && (pageSize >= 1 || pageSize <= 1000) && totalFilters <= 10; } Condition for a check of a valid page size is erroneous. Instead of the operator ||, one has to use &&. The corrected code:
      public override bool IsValid() { .... return base.IsValid() && (pageSize >= 1 && pageSize <= 1000) && totalFilters <= 10; } Possible division by zero
      PVS-Studio warning: V3064 CWE-369 Potential division by zero. Consider inspecting denominator '(float)(width - 1)'. ClothInspector.cs 249
      Texture2D GenerateColorTexture(int width) { .... for (int i = 0; i < width; i++) colors[i] = GetGradientColor(i / (float)(width - 1)); .... } The problem may occur when passing the value width = 1 into the method. In the method, it is not checked anyway. The method GenerateColorTexture is called in the code just once with the parameter 100:
      void OnEnable() { if (s_ColorTexture == null) s_ColorTexture = GenerateColorTexture(100); .... } So, there is no error here so far. But, just in case, in the method GenerateColorTexture the possibility of transferring incorrect width value should be provided.
      Paradoxical check
      PVS-Studio warning: V3080 CWE-476 Possible null dereference. Consider inspecting 'm_Parent'. EditorWindow.cs 449
      public void ShowPopup() { if (m_Parent == null) { .... Rect r = m_Parent.borderSize.Add(....); .... } } Probably, due to a typo, the execution of such code guarantees the use of the null reference m_Parent. The corrected code:
      public void ShowPopup() { if (m_Parent != null) { .... Rect r = m_Parent.borderSize.Add(....); .... } } The same error occurs later in the code:
      PVS-Studio warning: V3080 CWE-476 Possible null dereference. Consider inspecting 'm_Parent'. EditorWindow.cs 470
      internal void ShowWithMode(ShowMode mode) { if (m_Parent == null) { .... Rect r = m_Parent.borderSize.Add(....); .... } And here's another interesting bug that can lead to access by a null reference due to incorrect check:
      PVS-Studio warning: V3080 CWE-476 Possible null dereference. Consider inspecting 'objects'. TypeSelectionList.cs 48
      public TypeSelection(string typeName, Object[] objects) { System.Diagnostics.Debug.Assert(objects != null || objects.Length >= 1); .... } It seems to me that Unity developers quite often make errors related to misuse of operators || and && in conditions. In this case, if objects has a null value, then this will lead to a check of second part of the condition (objects != null || objects.Length >= 1), which will entail the unexpected throw of an exception. The error should be corrected as follows:
      public TypeSelection(string typeName, Object[] objects) { System.Diagnostics.Debug.Assert(objects != null && objects.Length >= 1); .... } Early nullifying
      PVS-Studio warning: V3080 CWE-476 Possible null dereference. Consider inspecting 'm_RowRects'. TreeViewControlGUI.cs 272
      public override void GetFirstAndLastRowVisible(....) { .... if (rowCount != m_RowRects.Count) { m_RowRects = null; throw new InvalidOperationException(string.Format("....", rowCount, m_RowRects.Count)); } .... } In this case, the exception throw (access by the null reference m_RowRects) will happen when generating the message string for another exception. Code might be fixed, for example, as follows:
      public override void GetFirstAndLastRowVisible(....) { .... if (rowCount != m_RowRects.Count) { var m_RowRectsCount = m_RowRects.Count; m_RowRects = null; throw new InvalidOperationException(string.Format("....", rowCount, m_RowRectsCount)); } .... } One more error when checking
      PVS-Studio warning: V3080 CWE-476 Possible null dereference. Consider inspecting 'additionalOptions'. MonoCrossCompile.cs 279
      static void CrossCompileAOT(....) { .... if (additionalOptions != null & additionalOptions.Trim().Length > 0) arguments += additionalOptions.Trim() + ","; .... } Due to the fact that the & operator is used in a condition, the second part of the condition will always be checked, regardless of the result of the check of the first part. In case if the variable additionalOptions has the null value, the exception throw is inevitable. The error has to be corrected, by using the operator && instead of &.
      As we can see, among the warnings with the number V3080 there are rather insidious errors.
      Late check
      PVS-Studio warning: V3095 CWE-476 The 'element' object was used before it was verified against null. Check lines: 101, 107. StyleContext.cs 101
      public override void OnBeginElementTest(VisualElement element, ....) { if (element.IsDirty(ChangeType.Styles)) { .... } if (element != null && element.styleSheets != null) { .... } .... } The variable element is used without preliminary check for null. While later in the code this check is performed. The code probably needs to be corrected as follows:
      public override void OnBeginElementTest(VisualElement element, ....) { if (element != null) { if (element.IsDirty(ChangeType.Styles)) { .... } if (element.styleSheets != null) { .... } } .... } In code there are 18 more errors. Let me give you a list of the first 10:
      V3095 CWE-476 The 'property' object was used before it was verified against null. Check lines: 5137, 5154. EditorGUI.cs 5137 V3095 CWE-476 The 'exposedPropertyTable' object was used before it was verified against null. Check lines: 152, 154. ExposedReferenceDrawer.cs 152 V3095 CWE-476 The 'rectObjs' object was used before it was verified against null. Check lines: 97, 99. RectSelection.cs 97 V3095 CWE-476 The 'm_EditorCache' object was used before it was verified against null. Check lines: 134, 140. EditorCache.cs 134 V3095 CWE-476 The 'setup' object was used before it was verified against null. Check lines: 43, 47. TreeViewExpandAnimator.cs 43 V3095 CWE-476 The 'response.job' object was used before it was verified against null. Check lines: 88, 99. AssetStoreClient.cs 88 V3095 CWE-476 The 'compilationTask' object was used before it was verified against null. Check lines: 1010, 1011. EditorCompilation.cs 1010 V3095 CWE-476 The 'm_GenericPresetLibraryInspector' object was used before it was verified against null. Check lines: 35, 36. CurvePresetLibraryInspector.cs 35 V3095 CWE-476 The 'Event.current' object was used before it was verified against null. Check lines: 574, 620. AvatarMaskInspector.cs 574 V3095 CWE-476 The 'm_GenericPresetLibraryInspector' object was used before it was verified against null. Check lines: 31, 32. ColorPresetLibraryInspector.cs 31 Wrong Equals method
      PVS-Studio warning: V3115 CWE-684 Passing 'null' to 'Equals' method should not result in 'NullReferenceException'. CurveEditorSelection.cs 74
      public override bool Equals(object _other) { CurveSelection other = (CurveSelection)_other; return other.curveID == curveID && other.key == key && other.type == type; } Overload of the Equals method was implemented carelessly. One has to take into account the possibility of obtaining null as a parameter, as this can lead to a throw of an exception, which hasn't been considered in the calling code. In addition, the situation, when _other can't be cast to the type CurveSelection, will lead to a throw of an exception. The code has to be fixed. A good example of the implementation of Object.equals overload is given in the documentation.
      In the code, there are other similar errors:
      V3115 CWE-684 Passing 'null' to 'Equals' method should not result in 'NullReferenceException'. SpritePackerWindow.cs 40 V3115 CWE-684 Passing 'null' to 'Equals' method should not result in 'NullReferenceException'. PlatformIconField.cs 28 V3115 CWE-684 Passing 'null' to 'Equals' method should not result in 'NullReferenceException'. ShapeEditor.cs 161 V3115 CWE-684 Passing 'null' to 'Equals' method should not result in 'NullReferenceException'. ActiveEditorTrackerBindings.gen.cs 33 V3115 CWE-684 Passing 'null' to 'Equals' method should not result in 'NullReferenceException'. ProfilerFrameDataView.bindings.cs 60 Once again about the check for null inequality
      PVS-Studio warning: V3125 CWE-476 The 'camera' object was used after it was verified against null. Check lines: 184, 180. ARBackgroundRenderer.cs 184
      protected void DisableARBackgroundRendering() { .... if (camera != null) camera.clearFlags = m_CameraClearFlags; // Command buffer camera.RemoveCommandBuffer(CameraEvent.BeforeForwardOpaque, m_CommandBuffer); camera.RemoveCommandBuffer(CameraEvent.BeforeGBuffer, m_CommandBuffer); } When the camera variable is used the first time, it is checked for null inequality. But further along the code the developers forget to do it. The correct variant could be like this:
      protected void DisableARBackgroundRendering() { .... if (camera != null) { camera.clearFlags = m_CameraClearFlags; // Command buffer camera.RemoveCommandBuffer(CameraEvent.BeforeForwardOpaque, m_CommandBuffer); camera.RemoveCommandBuffer(CameraEvent.BeforeGBuffer, m_CommandBuffer); } } Another similar error:
      PVS-Studio warning: V3125 CWE-476 The 'item' object was used after it was verified against null. Check lines: 88, 85. TreeViewForAudioMixerGroups.cs 88
      protected override Texture GetIconForItem(TreeViewItem item) { if (item != null && item.icon != null) return item.icon; if (item.id == kNoneItemID) // <= return k_AudioListenerIcon; return k_AudioGroupIcon; } An error, that in some cases leads to an access by a null link. The execution of the condition in the first block if enables the exit from the method. However, if this does not happen, then there is no guarantee that the reference item is non-zero. Here is the corrected version of the code:
      protected override Texture GetIconForItem(TreeViewItem item) { if (item != null) { if (item.icon != null) return item.icon; if (item.id == kNoneItemID) return k_AudioListenerIcon; } return k_AudioGroupIcon; } In the code there are 12 similar errors. Let me give you a list of the first 10:
      V3125 CWE-476 The 'element' object was used after it was verified against null. Check lines: 132, 107. StyleContext.cs 132 V3125 CWE-476 The 'mi.DeclaringType' object was used after it was verified against null. Check lines: 68, 49. AttributeHelper.cs 68 V3125 CWE-476 The 'label' object was used after it was verified against null. Check lines: 5016, 4999. EditorGUI.cs 5016 V3125 CWE-476 The 'Event.current' object was used after it was verified against null. Check lines: 277, 268. HostView.cs 277 V3125 CWE-476 The 'bpst' object was used after it was verified against null. Check lines: 96, 92. BuildPlayerSceneTreeView.cs 96 V3125 CWE-476 The 'state' object was used after it was verified against null. Check lines: 417, 404. EditorGUIExt.cs 417 V3125 CWE-476 The 'dock' object was used after it was verified against null. Check lines: 370, 365. WindowLayout.cs 370 V3125 CWE-476 The 'info' object was used after it was verified against null. Check lines: 234, 226. AssetStoreAssetInspector.cs 234 V3125 CWE-476 The 'platformProvider' object was used after it was verified against null. Check lines: 262, 222. CodeStrippingUtils.cs 262 V3125 CWE-476 The 'm_ControlPoints' object was used after it was verified against null. Check lines: 373, 361. EdgeControl.cs 373 The choice turned out to be small
      PVS-Studio warning: V3136 CWE-691 Constant expression in switch statement. HolographicEmulationWindow.cs 261
      void ConnectionStateGUI() { .... HolographicStreamerConnectionState connectionState = PerceptionRemotingPlugin.GetConnectionState(); switch (connectionState) { .... } .... } The method PerceptionRemotingPlugin.GetConnectionState() is to blame here. We have already come across it when we were analyzing the warnings V3022:
      internal static HolographicStreamerConnectionState GetConnectionState() { return HolographicStreamerConnectionState.Disconnected; } The method will return a constant. This code is very strange. It needs to be paid attention.

      Conclusions
      I think we can stop at this point, otherwise the article will become boring and overextended. Again, I listed the errors that I just couldn't miss. Sure, the Unity code contains a big number of the erroneous and incorrect constructions, that need to be fixed. The difficulty is that many of the issued warnings are very controversial and only the author of the code is able to make the exact "diagnosis" in each case.
      Generally speaking about the Unity project, we can say that it is rich for errors, but taking into account the size of its code base (400 thousand lines), it's not so bad. Nevertheless, I hope that the authors will not neglect the code analysis tools to improve the quality of their product.
      Use PVS-Studio and I wish you bugless code!
       
    • By ethancodes
      I feel like I should know this, but I tried looking it up to make sure I wasn't confusing myself, and couldn't seem to find a clear answer that made sense to me. When assigning something like this:
      GridSquare randomPosition; randomPosition = gridPositions[Random.Range(0,gridPositions.GetLength(0)),Random.Range(0,gridPositions.GetLength(1))]; Am I putting a copy of the GridSquare in gridPositions into the GridSquare randomPosition, or is randomPosition referencing the GridSquare at this location? If it's a copy, is there a way to reference it, like a pointer in c++, because that's what I want to do.
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Virtual Memory

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I'm using C#, and trying to test whether Windows has virtual memory enabled or not.  I just need a function that can return a bool for this.  Does anyone know of one?  I know it's possible because I remember trying to play a game once and getting an error that said I needed to enable virtual memory.

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4 hours ago, Hodgman said:

You can't disable virtual memory,

Can't I?  Then what's this option called "No paging file"?

Anyway, the reason I want to check for this is because I want my program to only run if virtual memory is disabled (or I guess if the paging file is 0 bytes), otherwise it will give an error and exit.

Edited by myvraccount
I tried to include a screenshot but I guess it didn't work. Oh and also, is there a way to do it without importing a DLL or anything like that? I'm trying to keep my program files as small and simple as possible for distribution.

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I couldn't edit any more for some reason because I guess they imposed a stupid space limitation.

Anyway, come to think of it, then how did the game know whether I had virtual memory enabled or not?

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Edit on not noticing the C# tag :o
c# wise Im pretty sure something along the lines of (https://msdn.microsoft.com/en-us/library/system.diagnostics.process.pagedmemorysize64(v=vs.110).aspx) that is what you would want

 

In terms of wanting to check the maximum allowed virtual memory / pagefile size your application is allowed (https://msdn.microsoft.com/en-us/library/windows/desktop/aa366589(v=vs.85).aspx) that is a link to the GlobalMemoryStatus which returns a struct that has that info available in it.

it wont be able to show if its "enabled" or not, since it always is enabled.. you just change the size, but im guessing the game called something similar to that and then had a condition of if the size is 0 .... much like what you are wanting to do
 

Edited by GibbonThatCodes

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Correct me if I'm wrong (and I may well be) but the function in the first link actually seems to tell me how much virtual memory the program/process is actually using.  I only want to know the total size the the entire swap file or whatever you want to call it.  As in, how much is allocated for the whole computer to be allowed to use at maximum.

 

But the way you described it, it seems like that's what the second link is doing?  Did you accidentally say it backwards?  And as for the structure mentioned in the second link, I looked up the ullTotalPageFile, which seems like it should be for the whole system, but according to a link I followed from there, it seems to be for just the current process, so maybe that's an accurate description after all.

 

In any case, the only thing I need is the whole maximum amount set for virtual memory for the whole system (the "Maximum size (MB)" in the virtual memory properties window).  So whatever way I can get that would be great!  I prefer not to have to use a DLL but I will if I must.  Thanks a lot.

And the number needs to exclude the size of RAM.

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1 hour ago, myvraccount said:

Can't I?  Then what's this option called "No paging file"?

That disables demand paging not virtual memory... virtual memory is used to protect each applications memory space from each other.  While demand paging allows you to use more memory than physically available.

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2 hours ago, myvraccount said:

Can't I?  Then what's this option called "No paging file"?

 

Virtual memory, the general computing concept, is about providing a mapping to actual physical memory addresses from a (potentially larger) virtual (that is, "pretend") address space. This is a core OS feature in just about every modern operating system, and cannot be disabled. It is the thing that lets you (a) have an object at "address X" while another process also thinks it has a wholly different object at "address X," or allow both processes to think they're loading at the same address in memory when obviously they cannot be and (b) address the entire range of the address space even though you don't actually have that address space physically, assuming you don't address it all at once. It also provides other benefits, like memory protection via isolation.

You can't turn this feature off.

Colloquially, "virtual memory" is sometimes used in the context of Windows to refer to the page file and its size. This is a bit of a misnomer, as the use of a page file in the implementation of virtual memory is an optional implementation detail. However, since the Windows control panel for controlling the page file puts it under the "virtual memory" heading, and there are no other controls in that section, it's a term that kinda sticks. The page file is a mechanism to allow the OS to set aside memory that is in-use (but not immediately in use right now) on the disk in order to make room in physical memory and thus preserve the illusion of a larger virtual memory space.

So what you seem to be asking for is detecting the size of the page file. You probably cannot do this exactly the way you want, but if you call GetPerformanceInfo, you can read the CommitLimit member of the PERFORMANCE_INFO structure it fills out. This will tell you the global limit on pages that can be committed by the system without causing the page file to grow. You can multiply this by the size of a page file ("PageSize") to get a value in bytes. This will include physical RAM, which you'd need to subtract out potentially, depending on what you're doing. It's also not going to report what the page file is allowed to grow to.

2 hours ago, myvraccount said:

Anyway, come to think of it, then how did the game know whether I had virtual memory enabled or not?

There's a good chance they didn't, since they used the term "virtual memory." Now, perhaps they picked that term because of the reason I outlined above, where it's fallen into colloquial use among Windows users as a synonym of the page file, and they wanted to make sure users understood what exactly was "enabled." 

But my bet would be that they just made some calls into GetPerformanceInfo or GlobalMemoryStatusEx, read some numbers from it, maybe did some subtraction or other potentially-fuzzy math, and determined based on that whether or not the page file was enabled. I would not by default trust that the wording of that dialog means you can perform precisely the check you're thinking about performing.

Why do you only want your program to run if the page file is disabled, exactly?

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jpetrie, thanks for the info.  It's enlightening.  I was under the impression that what you're referring to a virtual memory, in terms of address re-mapping, was actually called protected mode addressing (at least that's what they called it when I studied assembly language for 68000 processors), but supposedly there are "rings" on PC, and the lower ones use that.  I don't know.

 

Anyway, the reason I do not want the program running if virtual memory (or demand paging, or whatever it's really called) is enabled (or is greater than 0 bytes for maximum size), is because it's a huge security flaw!  If a program encrypts anything before saving, then un-encrypted data will never exist on the hard drive, but if this mechanism can arbitrarily save anything in RAM onto the hard drive, that's very dangerous!

 

Also, I'm inclined to believe that there must be some way to do it, because after all, Windows keeps track of that information, so it must be stored somewhere right?

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10 minutes ago, myvraccount said:

Anyway, the reason I do not want the program running if virtual memory (or demand paging, or whatever it's really called) is enabled (or is greater than 0 bytes for maximum size), is because it's a huge security flaw!  If a program encrypts anything before saving, then un-encrypted data will never exist on the hard drive, but if this mechanism can arbitrarily save anything in RAM onto the hard drive, that's very dangerous!

This doesn't seem like a great reason to do this, but whatever. That unencrypted data can be read right out of RAM just as easily as reading it from the page file for somebody who is interested. There are also ways to ensure that a page file is cleared when users log out, and so on; these are all security-policy-level issues that should be in the domain of the user or the system administrator.

But if you want to make your application that user-hostile, that's your business.

10 minutes ago, myvraccount said:

Also, I'm inclined to believe that there must be some way to do it, because after all, Windows keeps track of that information, so it must be stored somewhere right?

No.

Along the same vein, Windows knows what your password is, right? Otherwise how do you log in. That doesn't mean the OS provides you a good, old-fashioned, "GiveMeTheUserPasswordInPlainText()" API you can call.

You're correct that this information is stored someplace. You might be correct that you can get at it somehow, that it's not flat-out inaccessible to user mode code. However, I know of no documented mechanism to do so, offhand, and if you're worried about security, doing this in an undocumented fashion is basically shooting yourself in the foot, so there's that.

 

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