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Usually a pixel is identified by the triple {X,Y, Color} each of the triple member can usually be represented using an int value.
So, in principle, you cannot directly convert a double into a pixel. What do you really intend to do?
If the Lord God Almighty had consulted me before embarking upon the Creation, I would have recommended something simpler.
-- Alfonso the Wise, 13th Century King of Castile.
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basically i want to draw x and y cordinates from an access database , i m using double data type, i may have float, but to draw i want to have pixels. so i need that conversion logic.
nill
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So you are having X,Y points as double/float and those values are stored in a DB.
Whts the problem now, typecast the values to 'int' and plot the detail.
But i don't know, hw you get the Color value for the cooridinate as our pal mentioned in the previous post.
Do your Duty and Don't expect the Result
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there's nothing logical in having floating point data types to store integers (moreover, such data types may loose the integers precision)...
please explain clearly what you have, because it seems that no one here understand your need exactly.
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simple yet im drawing a picture by using double the x and y cordinates.but i need definite integers to draw. and wish to draw in pixels , the image is having million of x and y.
so suggest what should i do to draw in pixels.
nill
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kindd wrote: so suggest what should i do to draw in pixels.
Using This[^] ?
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simple yet im drawing a picture by using double the x and y cordinates.but i need definite integers to draw. and wish to draw in pixels , the image is having million of x and y.
so suggest what should i do to draw in pixels.
nill
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please delete this post, i already saw your answer and replied to you
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toxcct wrote: there's nothing logical in having floating point data types to store integers (moreover, such data types may loose the integers precision)...
This sounds backwards. Floating point data types have more precision than integers so what exactly is being lost?
"Approved Workmen Are Not Ashamed" - 2 Timothy 2:15
"Judge not by the eye but by the heart." - Native American Proverb
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due to how floating point manage their memory, they don't store exact values but approximations.
they can store larger numbers, but with less precision... knowing this, that's normal to encounter a 1.9999999999999 in a float we actually assigned a 2
i can't find the exact link to what i affirm, but i hope some here understand what i mean and can provide a relevant link.
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I see what you are saying, and I was thinking of something completely different. Yes, I'm familiar with floating-point issues (storage vs. usage). That aside, it just seems silly to store "pixel" numbers in a floating-point variable. They're never going to be anything but whole.
"Approved Workmen Are Not Ashamed" - 2 Timothy 2:15
"Judge not by the eye but by the heart." - Native American Proverb
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Hi all,
My problem is i want to pass 4 variables in my SendMessage function.
What i am doing is pasing a single variable and the other three through structure like this :-
struct pasiin_val
{
int index;
CString url;
CString task_n;
};
void CMyThread::LogMessage(CString& logmsg)
{
if (m_pLogWnd)
{
pasiin_val obj_val;
obj_val.index = test_int;
obj_val.url = test_str;
obj_val.task_n = test_task_name;
m_pLogWnd->SendMessage(LOGMSG, (WPARAM)(CString*)&logmsg, obj_val);
}
}
when i am trying to do this its giving an error:-
error C2664: 'SendMessageA' : cannot convert parameter 3 from 'struct pasiin_val' to 'long'
can anybody help me in this......
thanks in advance
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sulabh_expert@rediffmail.com wrote: m_pLogWnd->SendMessage(LOGMSG, (WPARAM)(CString*)&logmsg, obj_val);
Modify this to,
m_pLogWnd->SendMessage(LOGMSG, (WPARAM)(&logmsg),(LPARAM)(&obj_val));
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now there is no error
But when i m accessing it my MessageMap function like this:-
recv_val *obj_recv = static_cast<recv_val*>(lparam);
its giving an error:-
error C2440: 'static_cast' : cannot convert from 'long' to 'struct recv_val *'
recv val is also a structure in other class in which i m having my messagemap
struct recv_val
{
CString Recv_URL;
CString Recv_name;
int Recv_index;
};
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sulabh_expert@rediffmail.com wrote: recv_val *obj_recv = static_cast(lparam);
See replies below.
-- modified at 3:29 Tuesday 20th March, 2007
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same error is coming..........
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Use reinterpret_cast.
recv_val *obj_recv = reinterpret_cast<recv_val*>(lParam);
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use reinterpret_cast<>() instead
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sulabh_expert@rediffmail.com wrote: struct recv_val
{
CString Recv_URL;
CString Recv_name;
int Recv_index;
};
Make sure the struct is properly defined. In the sender side you defined as int, CString, CString...
You can typecaste as below,
struct recv_val* pStruct = (recv_val*)(LPVOID)lParam;
Do your Duty and Don't expect the Result
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using C style cast is the simplicity mistake...;P
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thanku all my problem got solved..................
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I am facing same issue.
My message received at other side but I can access/cast structure at receiving side.
Can you specify which one solution works for you?
regards,
Divyang Mithaiwala
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sulabh_expert@rediffmail.com wrote: recv val is also a structure in other class in which i m having my messagemap
struct recv_val
{
CString Recv_URL;
CString Recv_name;
int Recv_index;
};
The structures must match.
"Approved Workmen Are Not Ashamed" - 2 Timothy 2:15
"Judge not by the eye but by the heart." - Native American Proverb
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Hi
All
I want to customize menu in my application in VC++ 6.0.In my application i want to display Marathi/Hindi font in menu, so how can i done it.
Regards
Atool
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