Re: DlangUI MouseEvent mouse delta
I am currently handling it like this: current = e.pos(); xdelta = current.x - previous.x; ydelta = current.y - previous.y; previous = current; I'm just wondering if there is a built in solution that I missed.
Re: C header file: tagged enumerations
On Tuesday, 26 April 2016 at 23:33:08 UTC, Stefan Koch wrote: static if (win32msi >= 500) . Won't work here because static if must have a complete declaration inside it, and the C pattern only has a few elements of the whole inside each #if. D doesn't handle this C pattern well... you basically have to rewrite the whole thing for each version. Personally, I just decide to support all of them and say the older versions with less declarations are less supported...
Re: C header file: tagged enumerations
On Tuesday, 26 April 2016 at 23:33:08 UTC, Stefan Koch wrote: On Tuesday, 26 April 2016 at 22:57:36 UTC, Jesse Phillips wrote: Windows tends to have these in their header files, what is the best way to translate them to D? [...] eunm win32msi = mixin(_WIN32_MSI); static if (win32msi >= 500) . Sorry forgot to mention that static if doesn't allow adding partial declarations, always need to be complete. Or to quote the compiler: "Error: basic type expected, not static"
Re: C header file: tagged enumerations
On Tuesday, 26 April 2016 at 22:57:36 UTC, Jesse Phillips wrote: Windows tends to have these in their header files, what is the best way to translate them to D? [...] eunm win32msi = mixin(_WIN32_MSI); static if (win32msi >= 500) .
C header file: tagged enumerations
Windows tends to have these in their header files, what is the
best way to translate them to D?
https://msdn.microsoft.com/en-us/library/whbyts4t.aspx
Example below. In general a named enum is close enough to the
same thing, but this example has additional enumerations added
based on the preprocessor.
Assuming _WIN32_MSI is defined for compile time, what is
recommended for creating this enum?
typedef enum tagINSTALLMESSAGE
{
// 12 others ...
INSTALLMESSAGE_INITIALIZE ,
INSTALLMESSAGE_TERMINATE ,
INSTALLMESSAGE_SHOWDIALOG ,
#if (_WIN32_MSI >= 500)
INSTALLMESSAGE_PERFORMANCE,
#endif // (_WIN32_MSI >= 500)
#if (_WIN32_MSI >= 400)
INSTALLMESSAGE_RMFILESINUSE ,
#endif // (_WIN32_MSI >= 400)
#if (_WIN32_MSI >= 450)
INSTALLMESSAGE_INSTALLSTART ,
INSTALLMESSAGE_INSTALLEND ,
#endif // (_WIN32_MSI >= 450)
} INSTALLMESSAGE;
DlangUI MouseEvent mouse delta
I am trying to know how much the mouse moves when clicking down
on a certain widget, but I can't figure out how. I noticed only a
mouse wheel delta property and nothing for the mouse pointer x,y
deltas since the click. I am looking to do something such as
if(e.lbutton().isDown() && !e.rbutton().isDown()) {
pitch -= e.dy();
}
Re: Lazy Generation of Random Sequence
On Tuesday, 26 April 2016 at 17:38:33 UTC, Nordlöw wrote: On Tuesday, 26 April 2016 at 11:09:42 UTC, Seb wrote: Btw if you do random generation at the moment, you should always be aware that it's super-easy to do an implicit copy if you pass around the rndGen So should I pass it by ref or const ref then? I guess both work fine, but this was just a warning for other case. The example that @WebDrake mentioned on his slides can happen too easily - a reason why we should fix it (which is on my agenda).
Re: Lazy Generation of Random Sequence
On Tuesday, 26 April 2016 at 11:09:42 UTC, Seb wrote: Btw if you do random generation at the moment, you should always be aware that it's super-easy to do an implicit copy if you pass around the rndGen So should I pass it by ref or const ref then?
Re: Lazy Generation of Random Sequence
On Tuesday, 26 April 2016 at 17:38:33 UTC, Nordlöw wrote: On Tuesday, 26 April 2016 at 11:09:42 UTC, Seb wrote: Btw if you do random generation at the moment, you should always be aware that it's super-easy to do an implicit copy if you pass around the rndGen So should I pass it by ref or const ref then? Doh. Const ref is of no use... just by ref then, right?
Re: Compare lambda expressions
There's no way to do this in D. There have been several proposals but nothing implemented as of yet.
Re: Garbage Collector : Ignoring a reference
Am Tue, 26 Apr 2016 13:35:37 + schrieb Begah : > When the screen switches to another screen ie from menu to the > game, > I want that the "button.png" texture is automaticly destroyed by > the gc. My ideological point of view is that you must not use non-deterministic garbage collection for resources. Neither for files, GUI widgets or textures. The garbage collector cannot look past its own confined environment (heap memory allocated by the D program and loaded D libraries) and will not have enough information to tell if the process is running out of file handles, backing buffer for widgets or texture memory on the graphics card. It only takes action, when its own heap is filling up or when you manually call GC.collect(). All the convenient 100% GC languages from Java to Python require the user to call ".close()" for files, ".dispose()/.Destroy()" for widgets, etc. Reference counting is the correct approach. It makes using external resources safe and convenient by removing the need for manual lifetime management. Cyclic references cannot exist in the D code in this scenario. The texture constructor: - sets ref count to 1 - adds texture to hash map The copy constructor: - increments the ref count The destructor: - decrements the ref count - if ref count reaches 0: - removes the texture from the hash table - destroys the texture data -- Marco
Compare lambda expressions
Hi all!
Not sure, if this belongs directly to the D language, or it is
rather maths, but:
given to delegate generating functions and a main
auto func1(int arg)
{
bool delegate(int x) dg;
dg = (x) => arg * x;
return dg;
}
auto func2(int arg)
{
bool delegate(int x) dg;
dg = (x) => arg * x * x / x;
return dg;
}
void main()
{
auto dgf1 = func1(4);
writeln(dgf1(2));
auto dgf2 = func2(4);
writeln(dgf2(2));
writeln(dgf1 == dgf2);
}
the last line gives false, either in this form, as well with
.ptr, as well with .funcptr.
The question is, how to say, whether two lambda expressions are
the same?
What if the lambda expressions are predicates? This case would be
more important for me...
I understand, that there is only a little hope to get answer
other then "impossible", even for the constrained case. In such a
case, I have another opportunity:
Say, I define two lambda functions as strings in, say a json
file. I'm going to parse them and build functions out of them.
How to force the input in a unified manner? In such a case, I
could compare the given strings with some weird regular
expression...
So, the question for this case is:
Is there some normalized form of writing a lambda expression? Any
literature would be more then sufficient as an answer...
Many thanks in advance :)
Re: Garbage Collector : Ignoring a reference
Thus, i need a way to tell the gc to ignore the reference ( or something similar ) in that hashmap. So, having pointer that doesn't hold a reference isn't that hard (store it in memory region that is unreachable to gc), but don't you need a way to tell if that pointer ins't dangling, beyond initial problem?
Re: Garbage Collector : Ignoring a reference
On 26.04.2016 15:35, Begah wrote: Nothing will reload. An example : I load a texture "button.png" in a class and draw it to the screen, When the screen switches to another screen ie from menu to the game, I want that the "button.png" texture is automaticly destroyed by the gc. But this will never happen because i still have a reference to it in my hashmap. Thus, i need a way to tell the gc to ignore the reference ( or something similar ) in that hashmap. How would you prevent reads of that now-invalid element of the hashmap?
Re: Garbage Collector : Ignoring a reference
On Tuesday, 26 April 2016 at 13:01:26 UTC, ciechowoj wrote: On Tuesday, 26 April 2016 at 09:07:59 UTC, Begah wrote: How could i tell the garbage collector to ignore the reference in the hashmap and to free it if there isn't any other reference that in my hashmap? You could always zero the reference in the hashmap, as it won't be valid after reload anyway... Nothing will reload. An example : I load a texture "button.png" in a class and draw it to the screen, When the screen switches to another screen ie from menu to the game, I want that the "button.png" texture is automaticly destroyed by the gc. But this will never happen because i still have a reference to it in my hashmap. Thus, i need a way to tell the gc to ignore the reference ( or something similar ) in that hashmap.
Re: Garbage Collector : Ignoring a reference
On Tuesday, 26 April 2016 at 09:07:59 UTC, Begah wrote: How could i tell the garbage collector to ignore the reference in the hashmap and to free it if there isn't any other reference that in my hashmap? You could always zero the reference in the hashmap, as it won't be valid after reload anyway...
Re: Garbage Collector : Ignoring a reference
On Tuesday, 26 April 2016 at 09:07:59 UTC, Begah wrote: I am trying to create an asset manager for my textures. I had the idea ( it may be a wrong idea ) to create a hashmap of my textures with a string as the key. When the program request a texture, it firts check if it is in the hashmap and then returns if it is : [...] What you want are "weak references". I don't think D supports them yet.
Re: Lazy Generation of Random Sequence
On Tuesday, 26 April 2016 at 10:50:27 UTC, Nordlöw wrote: On Tuesday, 26 April 2016 at 10:31:22 UTC, Nordlöw wrote: How do I lazily generate a sequence of random instances of type `T` as an `InputRange`? Ahh, I found it: import std.range : generate, take; import std.random : uniform; auto randomSamples = generate!(() => uniform!Key).take(n); I should have guessed that... Btw if you do random generation at the moment, you should always be aware that it's super-easy to do an implicit copy if you pass around the rndGen, see: http://dconf.org/2015/talks/wakeling.html
Re: Lazy Generation of Random Sequence
On Tuesday, 26 April 2016 at 10:31:22 UTC, Nordlöw wrote: How do I lazily generate a sequence of random instances of type `T` as an `InputRange`? Ahh, I found it: import std.range : generate, take; import std.random : uniform; auto randomSamples = generate!(() => uniform!Key).take(n); I should have guessed that...
Lazy Generation of Random Sequence
How do I lazily generate a sequence of random instances of type `T` as an `InputRange`?
traits getMember gives a deprecation warning
I'm using DMD 2.071 and am getting this new deprecation error:
source/screener/lib/syntax/semantics.d(42): Deprecation:
screener.lib.virtualmachine.functions.object is not visible from
module semantics
source/screener/lib/syntax/semantics.d(42): Deprecation:
screener.lib.virtualmachine.functions.object is not visible from
module semantics
source/screener/lib/syntax/semantics.d(42): Deprecation:
screener.lib.virtualmachine.functions.screener is not visible
from module semantics
source/screener/lib/syntax/semantics.d(42): Deprecation:
screener.lib.virtualmachine.functions.screener is not visible
from module semantics
The offendding line is this :
import screener.lib.virtualmachine.functions;
alias funcModule = screener.lib.virtualmachine.functions;
bool found = false;
foreach(m; __traits(allMembers, funcModule)) {
static if ((__traits(isStaticFunction,
__traits(getMember, funcModule, m)) || __traits(isTemplate,
__traits(getMember, funcModule, m))) && __traits(getProtection,
__traits(getMember, funcModule, m)) != "private")
{
The module 'screener.lib.virtualmachine.functions' defines
'public' functions/templates. How can i fix this?
Garbage Collector : Ignoring a reference
I am trying to create an asset manager for my textures. I had the
idea ( it may be a wrong idea ) to create a hashmap of my
textures with a string as the key. When the program request a
texture, it firts check if it is in the hashmap and then returns
if it is :
Texture[string] textures;
Texture loadTexture(string filename) {
if(filename in textures)
return textures[filename]
else
// Load image and put it in hashmap
}
Warning : I haven't tested if it actually doesn't work, but
thinking about it, i think it should not.
My problem is that i return a reference of the texture to the
program, but i keep one to myself and i want to free the texture
if my program isn't using it anymore ( no more reference to it ).
The problem i see, is that i will always have atleast one
reference to the texture in my hashmap, but i want the garbage
collector to ignore that reference and to free the texture if
there are no more references anywhere in my program ( except in
the hashmap ).
How could i tell the garbage collector to ignore the reference in
the hashmap and to free it if there isn't any other reference
that in my hashmap?
