After compiling a ShaderProgram if it doesn't compile I print the log.
However, I can't find a way to tell if the error is in the fragment or vertex shader.
Here I put an error in the frag shader:
0:1(1): error: syntax error, unexpected NEW_IDENTIFIER
This error is in the vert shader:
0:1(1): error: syntax error, unexpected NEW_IDENTIFIER
is there a way to show more detail about where the error is?
Looking at the Libgdx ShaderProgram source I couldn't seem to see one: http://libgdx.badlogicgames.com/nightlies/docs/api/com/badlogic/gdx/graphics/glutils/ShaderProgram.html
Not ideal, but: You can add a blank line at the beginning of one of the two shaders. Then see if the line number for the error changes to determine which one it applies to.
Related
I'm running this on Wolfram cloud. Here's the code
ClearAll[s,l,L,L1,M1,Mt,m,M,vym,vxm,wp,J,Meff,theta,omega]
Rr = {{Cos[theta],-Sin[theta],0},{Sin[theta],Cos[theta],0},{0,0,1}};
Wm = {0,0,omega};
This is obviously part of a larger code, but just this much is enough to create the error. If I remove any line, the error disappears. I can't for the life of me figure out where a syntax error could be in here!
When my program stops working due to division by 0 then is it considered error or failure?
Error is called when a human action produces an incorrect result. Failure is when we get different result than expected. I'm just wondering if the unexpected stop from program is a error by human or failure of the program?
It is considere as an error. Or we can also called this an exception. And if u dont want to prevent this u can use exception handling.
Depending on the programming environment and the type of number (e.g. floating point, integer) being divided by zero, it may generate positive or negative infinity, generate an exception, generate an error message, cause the program to terminate.
It is a type of failure when it is in compile time but it is an error because usually this type of an error occur when the program is compiled and then executed
I'm trying to do some 3D boolean operations with CGAL. I have successfully converted my polyhedra to nef polyhedra. However, when ever I try doing a simple union, I get an assertion fail on line 286 of SM_overlayer.h:
CGAL error: assertion violation!
Expression : G.mark(v1,0)==G.mark(v2,0)&& G.mark(v1,1)==G.mark(v2,1)
File : ./CGAL/include/CGAL/Nef_S2/SM_overlayer.h
Line : 287
I tried searching the documentation for "mark". Apparently it is a template argument on the Nef_polyhedron_3" that defaults to bool. However the documentation also says it is not implemented and that you shouldn't mess with it. I am a bit confused why there is even an assertion on some unimplemented feature. I tried simply commenting out the assertion, but it simply goes on to fail at a later point.
I am using the following kernel and typedefs as it was the only example I could find that allowed doubles in the construction of the meshes.
typedef CGAL::Exact_predicates_exact_constructions_kernel Kernel;
typedef CGAL::Nef_polyhedron_3<Kernel> Nef_polyhedron;
typedef CGAL::Polyhedron_3<Kernel> Polyhedron;
I used CGAL 4.6.3 installed with the exe installer. I have also tried the 4.7 beta and I get the same exception(at line 300 instead though).
Related github issue: https://github.com/CGAL/cgal/issues/353
EDIT: The issue turned out to be with the meshes. The meshes I were using had self intersections. Thus, even though is_valid, is_closed and is_triangular returned true, the mesh was in valid for conversion to a nef polyhedron. From CGAL 4.7. The Polygon mesh processing package has been introduced which contains this which can be used to check for self intersections.
I am porting a game engine that works perfectly on different platforms (Windows, iOS, Playbook, BB10, Android) to NaCl
2d renders correctly but some 3d Objects don't show or are rendered really strange and i get the following con
[.PPAPIContext]GL ERROR :GL_INVALID_FRAMEBUFFER_OPERATION : BackTexture::AllocateStorage: <- error from previous GL command (index):1
[.PPAPIContext]GL ERROR :GL_INVALID_OPERATION : glVertexAttribPointer: stride not valid for type (index):1
[.PPAPIContext]GL ERROR :GL_INVALID_OPERATION : glVertexAttribPointer: offset not valid for type (index):1
[.PPAPIContext]GL ERROR :GL_INVALID_OPERATION : glDrawElements: attempt to access out of range vertices in attribute 0 (index):1
[.PPAPIContext]GL ERROR :GL_INVALID_OPERATION : glVertexAttribPointer: stride not valid for type (index):1
[.PPAPIContext]GL ERROR :GL_INVALID_OPERATION : glVertexAttribPointer: offset not valid for type (index):1
[.PPAPIContext]GL ERROR :GL_INVALID_OPERATION : glVertexAttribPointer: stride not valid for type (index):1
[.PPAPIContext]GL ERROR :GL_INVALID_OPERATION : glVertexAttribPointer: offset not valid for type (index):1
[.PPAPIContext]GL ERROR :GL_INVALID_OPERATION : glVertexAttribPointer: stride not valid for type
And it repeats indefinitely.
Again, the same render code is used for different platforms and it works just fine. Is there a special consideration to be taken into account when porting to NaCl? Any ideas about what i should focus on to try find the issue?
As far as i can understand, there's a problem with the shader 0 (the vertex shader) and indeed the vertices of some objects are all over the place.
Thanks! :)
For security reasons, Chrome validates many GL operations that other drivers may not. It's a bit of work, but you might try searching the Chromium codebase using http://cs.chromium.org to find the error messages.
Here's what I found:
BackTexture::AllocateStorage: <- error from previous GL command
This one is tricky to follow. As it says, some previous GL command failed before BackTexture::AllocateStorage was called. I looked through the rest of the file, and it's not clear to me what command is failing here, but from the error value it is framebuffer related.
glVertexAttribPointer: stride not valid for type and glVertexAttribPointer: offset not valid for type
These are pretty clear -- the stride and offset values are not divisible by the component size. It would be useful to see your calls to glVertexAttribPointer.
glDrawElements: attempt to access out of range vertices in attribute 0
VertexAttrib::CanAccess is failing, which checks whether the attrib is enabled, not deleted, and if the vertex index that you're trying to access is valid. As the error says, you are likely referencing a vertex outside of the valid range.
To debug this, I'd narrow down the calls to glDrawElements and glVertexAttribPointer and try to find which one is failing, then I'd add some printf calls to see what values are being passed.
Good luck!
Consider the following class:
class Xyz {
public int count;
public void numZero (int[] x) {
// Effects: if x == null throw NullPointerException
// else return the number of occurrences of 0 in x
int count = 0;
for (int i = 1; i < x.length; i++) //we have a bug here
{
if (x[i] == 0)
{
count++;
}
}
this.count = count;
}
}
I'm trying to wrap my head about what Fault, Error and Failure really mean.
Fault
From what I've come to understand, a Fault in this context would be a flaw in the code's written logic.
So in this case the Fault would be the fact that the code instructs the computer to start iterating over all elements of v with a start index of 1 instead of the expected 0.
Error
When running the above method, we always get an Error but in once instance (when v.length == 0), as what we really want is to iterate over all elements of x, but since we're starting with i = 1, that is not really happening.
With an empty vector as input, as we don't enter the for loop, so our incorrect code isn't run, meaning that the Error doesn't happen, and everything happens as should in theory.
Failure
Since our code has a Fault that in execution-time will almost always manifest in a Error, we only have a Failure when we effectively see the incorrect output.
Assuming that an Error effectively happened in my program, we only have a Failure if it is in some way visible to the outside world. That is, had I private int count; instead of public int count; I'd never ever have an Error in my class (of course it'd be the most useless class ever!). Is this right?
Is everything I said correct or am I erring in something?
Thanks
Failure: A difference from the expected result. This is the problem
you observe.
Fault: The cause of the failure.
Error: The mistake which caused the fault to occur. e.g, typos.
An example of failure, fault and error.
pre: param is an integer.
post: returns the product of the param multiplied by 2.
1. int double (int param) {
2. int result;
3. result = param * param;
4. return result;
5. }
• A call to double(3) returns 9, but the post condition says it should return 6.
• Result 9 represents a failure.
• The failure is due to the fault at line 3, ( "* param" is used instead of "* 2")
• The error is a typo, ( someone typed "* param" instead of "* 2" by mistake).
Why give three different labels for a "Bug"?
They help communicate how precisely you know what the problem is.
Saying "failure" means you know something is wrong but don't know the cause.
Saying "fault" means you know the cause, but don't know why the fault occurred.
Saying "Error" means you know why the fault occurred; e.g.: The coder was distracted by a firetruck passing by.
You could ask, "But why did the person make a typo?" But that gets into into human factors and out of the scope of the question.
Source: Zhen Ming (Jack) Jiang - EECS 4413, Software Testing, York University.
First, a failure occurs whenever the actual service delivered by a system deviates from its expected service. Note that since even specifications can go wrong, the definition does not rely on them.
Second, an error is the part of the system state that may lead to a failure. The state of the system can go wrong but never reach the output, thus not lead to a failure.
Third, a fault is the cause of an error. It can be a design fault, a cosmic ray or whatever. If, as you point out, the fault is not activated, no error is produced.
Take a look at the basic concepts and terminology of dependability for more information.
Error is a deviation from the actual and the expected result. It represents the mistakes made by the people.
Faults are the result of an error. It is the incorrect step or process due to which the program or the software behaves in an unintended manner
Bug is an evidence of Fault in a program due to which program does not behave in an intended manner
Failure is an inability of the system or components to perform its required function. Failure occurs when Faults executes
Defect is said to be detected when Failure occurs.
There are a plurality of different definitions, the one I personally prefer is the following:
Fault -> Error -> Failure
Fault: The verified or hypothesized cause of an error (malfunctions, external interference, design errors).
Error: The manifestation of a fault within a program or data structure (difference between actual output and expected output).
Failure: The event that occurs when an error reaches the service interface, altering the service itself (leads to the inability of a system or component to perform required function according to its specification).
The Error in Error/Fault/Failure refers to the human error that introduced the problem. The human error was the incorrect thinking that caused the user to create an incorrect for statement in your example.
Errors are hard to measure or understand. It is difficult in many cases to know what the developer was thinking when the made the error that introduced the fault. That is why they like to differentiate between error and fault. We can see that there is a fault in the code, but it is hard to know why the error was created. It could be that the code was correct, and then during a subsequent change, the for loop was changed.
I always remember that an Error by a programmer leads to a fault in the code that results in a failure for the user. Not all errors result in a fault. Not all faults result in failures.
The software Fault refers to a bug in the code. And it is DURING the software activity.
While software Failure is when the system misbehaves. This is observed LATER than a fault.
Fault may be the cause for a Failure. Fault is "WHAT" and Failure is "WHEN".
Those are only fundamentals, but still I hope that it sheds some light on the matter.