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Edited from some code I found, but don't know why it works. Palette doesn't get used ever again after this code, but still gets applied to the image when compiled and ran?
Code:bmp.palette =(RGBQUAD*) ((BYTE*)bmp.bitmapInfo + sizeof(BITMAPINFOHEADER));
if(!fread(bmp.palette, sizeof(RGBQUAD), bmp.nColors, file))
What do you mean by "doesn't get used ever again"?Quote:
Originally Posted by zaryk
So you expect anyone to know what your entire program is doing, with the loops, functions, assignments, etc. that are being done, by posting only 2 lines of code?Quote:
but still gets applied to the image when compiled and ran?
Regards,
Paul McKenzie
Look, if you would think about the question, it means exactly what I am saying. It never gets used again; no where in the code is it used after that; ctrl-F, palette, nothing afterwards (3 entries) where it is declared and those two;
And if you don't know what 'applied' means?
well, no where in the code do you set bitmapInfo.bmiColors = palette, for example. WOW, you learned something today. Good Job!
There is nothing else that is related to the palette. So, I expect people to think, and not ask stupid questions when not even I understand. Unlike when I first started, I am pretty capable of finding out what codes to use and why it works or doesn't; your lucky I ask at all. It means that I am confident there is someone who actually thinks things through before asking questions, but no, Im always let down. The other code is irrelevant.
I have been looking over different examples of reading bitmapinfo and displaying the pic, and every example I find never actually used the palette; just read the palette in a for loop or similar to the code below. The palette on some may use it to printf() the rgb colors to the console, but nothing.
When I didnt use the code, already displayed, I got the myprog3.gif.
Then I added the code, already displayed, I got the myprog4.gif. Voila! It Works!
And this is besides the fact that most of the other code I looked at, once you comment out those lines of code that copy the palette from the image; when you run the program; it crashes OR doesn't display an image at all.
Go do some research and come back to me when your actually thinking.
You can start with this one:
http://www.cplusplus.com/files/winbmp.zip
I edited the line from it because I couldn't find any better, and easiest to change around while testing why mine was showing a irregular image.
Code:bmp.palette =(RGBQUAD*) ((BYTE*)bmp.bitmapInfo + sizeof(BITMAPINFOHEADER));
The palette is useful only for screens displaying no more than 256 colors. They are quite rare nowadays. Usually, we have 32 bits per pixel, or more.
The BMP file format might contain a palette. But nowadays, images are rarely created with a palette anymore.
So ... what exactly is bmp and what do you do with it afterwards? Do you write it to a .bmp file or maybe use it create a bitmap in memory? In which case, why would you not expect the pallette to be applied when you display the bitmap with the pallette in it?Quote:
Originally Posted by zaryk
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Originally Posted by zaryk
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Originally Posted by zaryk
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Originally Posted by zaryk
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Originally Posted by zaryk
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Originally Posted by zaryk
Wow ... just wow.Quote:
Originally Posted by zaryk
Grabs pop-corn and waits for Paul McKenzie to return.
:D :thumb:Quote:
Originally Posted by Zaccheus
*sigh*
Zacc:
This really isn't about my code, it's about every code I have looked at, including the one I provided, but if it makes you feel better, bmp is a struct. And its drawn to a window, just a plain gray window. bmp.bitmapinfo.bmColors isn't equal to anything, so unless your saying that it reads in automatically, then I might have a better understanding, but that doesn't explain when you add those lines that read in the palette, it makes the image correct.
And this is in a class.Code:struct BMP
{
int nColors;
RGBQUAD *palette;
BYTE *bitmapImage;
BITMAPINFO * bitmapInfo;
BITMAPFILEHEADER fileHeader;
BITMAPINFOHEADER infoHeader;
};
BMP bmp;
You want to see how the infoHeader is read in too?
Why don't you all open up the example, make a project from the .cpp and comment/uncomment out these lines:
Code://Palette=(RGBQUAD*)((char*)pbmi+sizeof(BITMAPINFOHEADER));
//bmpfile.read ((char*)Palette,sizeof (RGBQUAD) * (1<<BPP));
the example image it provides, turns black when you comment out those lines
the example image displays correctly when you uncomment out those lines
Here have tux bitmap:
the tux image turns irregular when you comment out those lines
the tux image displays correctly when you uncomment out those lines
Edit: Maybe, its a compiler problem, so fyi I use codeblocks.
Wow, good way to get help from someone who has a lot of experience here (22000+ posts, and "reputation beyond repute (3000+)").Quote:
Originally Posted by zaryk
Viggy
Even I can ask 3000+ stupid questions in 22k posts, and become reputable. So, I don't judge that meter as a comparison for intelligence or experience.
Well, then try it! And we all will see how fast you'll achieve it! :rolleyes:Quote:
Originally Posted by zaryk
Wait till I'm about 80yrs old, when my brain is too old to think about the questions.
You don't gain a reputation for asking questions, only answering them.Quote:
Originally Posted by zaryk
Viggy
Well, you are an optimist! :rolleyes:Quote:
Originally Posted by zaryk
Wow, I learned something! I am so glad you cleared that up. I wish I could tell the difference, tho.
Programming is an exact science. Terms such as "never gets used" means nothing without a full explanation of what you are referring to. That could mean anything from a pointer to this palette not being referenced anymore, to some loop that gets only done once, to who knows whatever. We are not mind readers or psychic.Quote:
Originally Posted by zaryk
The point is this -- you need to learn to ask questions with more detail, so that others who have no idea what you mean can understand fully. Posting two lines of code and asking "what's happening?" is not the way to ask a serious question in any programming forum, not just CodeGuru. It is, if not amatuerish, unprofessional to formulate a question like that and then insult others (which is against forum rules to do so) who are asking you for more details. It is no different than someone posting this:
and asking why their program only adds 1 to i only once and "never gets used", insults anyone asking for details, and then goes on about how their program has loops, while statements, function calls, ad nauseam.Code:int i = 0;
i += 1;
As to my experience, try 30 years of programming, and currently in the business of imaging and graphics, so I could have helped you, but I guess not. So next time, formulate a question that explains in detail what is the problem you're having, and not expect us to use divining rods and a crystal ball to figure out what you're talking about.
Regards,
Paul McKenzie
Palette doesn't get used ever again after this code, but still gets applied to the image when compiled and ran?
Your right. "That could mean anything from a pointer to this palette not being referenced anymore, to some loop that gets only done once, to who knows whatever. We are not mind readers or psychic."
But, let's think it through for a moment:
I give you a subject (palette), and I tell you it (palette) is never used again after this code. So, whether palette is a reference or pointer, it isn't used anymore.
I don't have an integer in the code to indicate a loop. And, I told you it's not used ever again after this code, so it won't be used in a for loop anywhere. Even if there is a loop before the 2 lines, palette would still need to be used after the code somewhere (EDIT: to set bitmapInfo.bmiColors = to palette, e.g.), whether a pointer or reference. But, then again, I say its not used again after this code; so nope, no for loop, no pointer, no reference.
I only post 2 lines; you should expect these 2 lines to be the only 2 lines relevant. (Tho it still has nothing to do with my code at all)
So, you have 30yrs of programming experience, but don't have analytical skills or grammar skills (context clues)?
What the **** dude? What are you expecting? Someone to confirm that some voodoo magic is messing with your code? No one can figure out what is wrong from the sparse code and description you've given. Either post relevant code that duplicates your problem, or just abandon the thread, but please lose the attitude.
Think, first of all. Use your programming skills to analyze (if/then) the question. And, you could go learn how to draw a bitmap to a screen, and plug the two lines that are relevant and duplicate the problem. And its really not a problem; just an understanding, the problem was fixed when I added those 2 lines in....well, there is an if statement, so logically there would be the block for the if statement, too; but, I'm not sure you all would be able to figure that out.Quote:
What the **** dude? What are you expecting? Someone to confirm that some voodoo magic is messing with your code? No one can figure out what is wrong from the sparse code and description you've given. Either post relevant code that duplicates your problem, or just abandon the thread, but please lose the attitude.
Plus, I don't have an attitude....your just reading it like I have an attitude. Read it as if informative. :D
EDIT: You can start with this: http://www.cplusplus.com/files/winbmp.zip . That will get you started.
Would you like to go over the thousands of posts here where persons post a few lines, thinking that what they post is what's wrong, when it turns out it's another part of the code that they didn't post that is in error? Or how about the thousands of posts where the poster says "I know I didn't do xxxx in my code", but when we finally get a look at their program, they did do xxxx in their code? Why should we treat your post any differently, given you only posted 2 lines?Quote:
Originally Posted by zaryk
If you want your post to be treated seriously, don't say "I know I didn't..." or "I know I did ..." plus give us one or two lines -- just post the entire code or function. Programmers do not believe anything until they see the code for themselves. This ensures that whoever is helping you is not on a wild goose chase or involved in an endless thread asking more and more questions.
Note that it was only after I asked for more information and you posted something with a little more info did you get any responses. At some point, someone was going to ask you to provide more information after your initial post -- this time it was me, next time, it will be someone else.
Insulting CodeGuru participants is against forum rules. Keep it up, and you will have a short stay here.Quote:
So, you have 30yrs of programming experience, but don't have analytical skills or grammar skills (context clues)?
I will say it once again -- programming is an exact science. You may not like it, but that's the way it is. If you can't take the time to formulate a proper question, then you should seek help from someone who is sitting at your computer looking at your code instead of asking one of us.
And no, it isn't our job to try and recreate your problem, whatever that problem is. That is your job to take the time to get the information in a form that has sufficient enough information for third-parties (such as the volunteers here) to answer your question as quickly as possible.
Regards,
Paul McKenzie
Ok..I was just asking a question, if you find that insulting you must not have confidence in your abilities....So, Ill show you the code from winbmp, just to make you feel better (raise your self-esteem), because it does the same thing as mine.
Code://winbmp.zip
// *************************************************************
// BMP LOAD EXAMPLE
// Written by Juan Soulie <[email protected]>
// *************************************************************
#include <windows.h>
#include <fstream>
char szAppName [] = "BMPLoad";
LRESULT CALLBACK WindowProc (HWND, UINT, WPARAM, LPARAM);
// **********
// class CRaster
// - Generic class for BMP raster images.
class CRaster {
public:
int Width,Height; // Dimensions
int BPP; // Bits Per Pixel.
char * Raster; // Bits of the Image.
RGBQUAD * Palette; // RGB Palette for the image.
int BytesPerRow; // Row Width (in bytes).
BITMAPINFO * pbmi; // BITMAPINFO structure
// Member functions (defined later):
int LoadBMP (char * szFile);
int GDIPaint (HDC hdc,int x,int y);
};
// **********
// Windows Main Function.
// - Here starts our demo program
int WINAPI WinMain ( HINSTANCE hInstance, HINSTANCE hPrevInstance,
LPSTR lpCmdLine, int nCmdShow )
{
HWND hwnd;
MSG msg;
WNDCLASS wc;
wc.style = CS_HREDRAW|CS_VREDRAW;
wc.lpfnWndProc = WindowProc;
wc.cbClsExtra = 0;
wc.cbWndExtra = 0;
wc.hInstance = hInstance;
wc.hIcon = LoadIcon (NULL, IDI_APPLICATION);
wc.hCursor = LoadCursor (NULL, IDC_ARROW);
wc.hbrBackground = (HBRUSH) (COLOR_WINDOW+1);
wc.lpszMenuName = NULL;
wc.lpszClassName = szAppName;
RegisterClass (&wc);
hwnd = CreateWindow (szAppName,"BMP Load",WS_OVERLAPPEDWINDOW,
CW_USEDEFAULT,CW_USEDEFAULT,CW_USEDEFAULT,CW_USEDEFAULT,
0,0,hInstance,0);
ShowWindow (hwnd,nCmdShow);
UpdateWindow (hwnd);
while (GetMessage(&msg,0,0,0))
{
TranslateMessage (&msg);
DispatchMessage (&msg);
}
return msg.wParam;
}
// **********
// Main Window Procedure.
// - Processes Window Messages
LRESULT CALLBACK WindowProc
(HWND hwnd, UINT message, WPARAM wParam, LPARAM lParam)
{
static CRaster bmp;
HDC hdc;
PAINTSTRUCT ps;
switch (message)
{
case WM_CREATE:
bmp.LoadBMP ("C:\\tux.bmp");
return 0;
case WM_PAINT:
hdc=BeginPaint (hwnd,&ps);
bmp.GDIPaint (hdc,10,10);
EndPaint (hwnd,&ps);
return 0;
case WM_DESTROY:
PostQuitMessage (0);
return 0;
}
return DefWindowProc (hwnd,message,wParam,lParam);
}
// **********
// CRaster::LoadBMPFile (FileName);
// - loads a BMP file into a CRaster object
// * supports non-RLE-compressed files of 1, 2, 4, 8 & 24 bits-per-pixel
int CRaster::LoadBMP (char * szFile)
{
BITMAPFILEHEADER bmfh;
BITMAPINFOHEADER bmih;
// Open file.
std::ifstream bmpfile (szFile , std::ios::in | std::ios::binary);
if (! bmpfile.is_open()) return 1; // Error opening file
// Load bitmap fileheader & infoheader
bmpfile.read ((char*)&bmfh,sizeof (BITMAPFILEHEADER));
bmpfile.read ((char*)&bmih,sizeof (BITMAPINFOHEADER));
// Check filetype signature
if (bmfh.bfType!='MB') return 2; // File is not BMP
// Assign some short variables:
BPP=bmih.biBitCount;
Width=bmih.biWidth;
Height= (bmih.biHeight>0) ? bmih.biHeight : -bmih.biHeight; // absoulte value
BytesPerRow = Width * BPP / 8;
BytesPerRow += (4-BytesPerRow%4) % 4; // int alignment
// If BPP aren't 24, load Palette:
if (BPP==24)
pbmi=(BITMAPINFO*)new char [sizeof(BITMAPINFO)];
else
{
pbmi=(BITMAPINFO*) new char[sizeof(BITMAPINFOHEADER)+(1<<BPP)*sizeof(RGBQUAD)];
Palette=(RGBQUAD*)((char*)pbmi+sizeof(BITMAPINFOHEADER));
bmpfile.read ((char*)Palette,sizeof (RGBQUAD) * (1<<BPP));
}
pbmi->bmiHeader=bmih;
// Load Raster
bmpfile.seekg (bmfh.bfOffBits, std::ios::beg);
Raster= new char[BytesPerRow*Height];
// (if height is positive the bmp is bottom-up, read it reversed)
if (bmih.biHeight>0)
for (int n=Height-1;n>=0;n--)
bmpfile.read (Raster+BytesPerRow*n,BytesPerRow);
else
bmpfile.read (Raster,BytesPerRow*Height);
// so, we always have a up-bottom raster (that is negative height for windows):
pbmi->bmiHeader.biHeight=-Height;
bmpfile.close();
return 0;
}
// **********
// CRaster::GDIPaint (hdc,x,y);
// * Paints Raster to a Windows DC.
int CRaster::GDIPaint (HDC hdc,int x=0,int y=0)
{
// Paint the image to the device.
return SetDIBitsToDevice (hdc,x,y, Width, Height, 0, 0, 0,Height,(LPVOID)Raster,pbmi,0);
}
Do you read your own posts? Where was I insulted by your question? It is your reaction to merely being asked to provide more information is where you start the insults. Your post was getting no responses, and was only responded to after I asked for more information.Quote:
Originally Posted by zaryk
No confidence, but I have the ability to contribute here for over a decade answering questions -- that alone puts that notion to rest. I won't bother going into my other credentials, because I'm humble (so humble that I don't even post my Microsoft MVP logo here). But it won't matter, because you know more than anyone here. :rolleyes:Quote:
you must not have confidence in your abilities....
I don't need "esteem raised" -- it should have been posted to help us answer your question.. All I asked you was for more information so that we can help you, but for some reason, you are hostile to the ones here who are helping you.Quote:
So, Ill show you the code from winbmp, just to make you feel better (raise your self-esteem),
If you want to know why the code does what it does, then here it is:
You create a CRaster object that is declared as static. That means that the lifetime of the object is perpetual, but can only be accessed within the WindowProc function.Code:// **********
// Main Window Procedure.
// - Processes Window Messages
LRESULT CALLBACK WindowProc
(HWND hwnd, UINT message, WPARAM wParam, LPARAM lParam)
{
static CRaster bmp;
This is where you are loading the bitmap within the WM_CREATE message. WM_CREATE is sent on window creation by the OS, so it's only called once.Code:switch (message)
{
case WM_CREATE:
bmp.LoadBMP ("C:\\tux.bmp");
return 0;
WM_PAINT message is sent whenever the client area of the window needs to be updated. Since the bmp object has been loaded with the bitmap, and bmp has not gone out of scope (because it is static), the bitmap is still valid, and you're just painting the area of the window with the bitmap.Code:case WM_PAINT:
hdc=BeginPaint (hwnd,&ps);
bmp.GDIPaint (hdc,10,10);
This code needs to be called only once, and it is called during the WM_CREATE message.Code:// **********
// CRaster::LoadBMPFile (FileName);
// - loads a BMP file into a CRaster object
// * supports non-RLE-compressed files of 1, 2, 4, 8 & 24 bits-per-pixel
int CRaster::LoadBMP (char * szFile)
{
See how simple that all was when you provide the information? So what was the tirade you had in your second post all about? Now do you understand how that bitmap need not be created over and over again, or do you need more explanation?
But let's take a look at your initial post, and the code you eventually posted. Do you think in your wildest dreams that anyone could come up with that final code from your original post? Were we supposed to somehow extrapolate from your first post CRaster, static variables, WM_CREATE, etc.?
Regards,
Paul McKenzie
It's useless wasting time answering a question about palettes and the window's bmp format if you don't know them, and it's useless arguing with people who don't know palettes and the window's bmp format.Yes, there is, but it is somewhat hidden. You have two fields in the BITMAPINFOHEADER:Quote:
Originally Posted by zaryk
1. biClrUsed
2. biBitCount
See http://msdn.microsoft.com/en-us/libr...76(VS.85).aspx
The code from winbmp is not correct. It has a bug about the palette.
You could have found better source codes. I learnt about bitmaps in a good old book called Ben Ezzell, Graphics Programming, Ziff Davis.
The bug is here:
A better code isCode:// If BPP aren't 24, load Palette:
if (BPP==24)
Code:if (bmih.biClrUsed == 0 || BPP >= 24)
Edit: It is very likely the value of BPP (biBitCount) is 32 in your image, because it is often 32 for images, nowadays, therefore your image would have no palette.
The program tries to read the palette with the line:
But, if BPP is 32, then 1<<BPP is out of the limits of a 32-bit integer (and not testing the limit is another bug of this ugly source code).Code:bmpfile.read ((char*)Palette,sizeof (RGBQUAD) * (1<<BPP))
I guess your compiler, and your environment will give you 0. So you have an empty palette. Then, with your additional line, you tell Windows to use an empty palette (or not to use the default palette), and that's why your code would work.
Re Edit: Or maybe I have not understood very well how the palette is taken into account into your program. Anyway, don't do 1<<32, and, in the first time, have a better test than if (BPP==24).
You quoted me, and then I thought you were talking about yourself when you said, "Insulting CodeGuru participants is against forum rules." You know, context clues.
EDIT: oliv, technically your right. But, those have nothing to do with what I have been trying to get an answer to.
I didn't write the provided code, and my code isn't based on that code. My code includes a gui class (global to WinMain) and a bitmap class (declared in gui)...and the bitmap class is used to subclass a static control (in the gui class) into a imagebox more or less.
images are 4 bit...and I know 24 and 32 bit images, don't have a palette. EDIT: Problem isn't with the images...I have images to test 1, 4, 8, 16, 24, 32 bits
Let me try this again, I don't care whether Craster is static or not, I don't care whether craster is in winproc. Whether Craster is global or not, it still displays the image, and the code is still good enough (tho shouldnt be required)
Pay attention to:
RGBQUAD * Palette; // RGB Palette for the image.
//Palette=(RGBQUAD*)((char*)pbmi+sizeof(BITMAPINFOHEADER));
//bmpfile.read ((char*)Palette,sizeof (RGBQUAD) * (1<<BPP));
nothing else
Code:
//winbmp.zip
// *************************************************************
// BMP LOAD EXAMPLE
// Written by Juan Soulie <[email protected]>
// *************************************************************
#include <windows.h>
#include <fstream>
char szAppName [] = "BMPLoad";
LRESULT CALLBACK WindowProc (HWND, UINT, WPARAM, LPARAM);
// **********
// class CRaster
// - Generic class for BMP raster images.
class CRaster {
public:
int Width,Height; // Dimensions
int BPP; // Bits Per Pixel.
char * Raster; // Bits of the Image.
RGBQUAD * Palette; // RGB Palette for the image.
int BytesPerRow; // Row Width (in bytes).
BITMAPINFO * pbmi; // BITMAPINFO structure
// Member functions (defined later):
int LoadBMP (char * szFile);
int GDIPaint (HDC hdc,int x,int y);
};
// **********
// Windows Main Function.
// - Here starts our demo program
int WINAPI WinMain ( HINSTANCE hInstance, HINSTANCE hPrevInstance,
LPSTR lpCmdLine, int nCmdShow )
{
HWND hwnd;
MSG msg;
WNDCLASS wc;
wc.style = CS_HREDRAW|CS_VREDRAW;
wc.lpfnWndProc = WindowProc;
wc.cbClsExtra = 0;
wc.cbWndExtra = 0;
wc.hInstance = hInstance;
wc.hIcon = LoadIcon (NULL, IDI_APPLICATION);
wc.hCursor = LoadCursor (NULL, IDC_ARROW);
wc.hbrBackground = (HBRUSH) (COLOR_WINDOW+1);
wc.lpszMenuName = NULL;
wc.lpszClassName = szAppName;
RegisterClass (&wc);
hwnd = CreateWindow (szAppName,"BMP Load",WS_OVERLAPPEDWINDOW,
CW_USEDEFAULT,CW_USEDEFAULT,CW_USEDEFAULT,CW_USEDEFAULT,
0,0,hInstance,0);
ShowWindow (hwnd,nCmdShow);
UpdateWindow (hwnd);
while (GetMessage(&msg,0,0,0))
{
TranslateMessage (&msg);
DispatchMessage (&msg);
}
return msg.wParam;
}
// **********
// Main Window Procedure.
// - Processes Window Messages
LRESULT CALLBACK WindowProc
(HWND hwnd, UINT message, WPARAM wParam, LPARAM lParam)
{
static CRaster bmp;
HDC hdc;
PAINTSTRUCT ps;
switch (message)
{
case WM_CREATE:
bmp.LoadBMP ("C:\\tux.bmp");
return 0;
case WM_PAINT:
hdc=BeginPaint (hwnd,&ps);
bmp.GDIPaint (hdc,10,10);
EndPaint (hwnd,&ps);
return 0;
case WM_DESTROY:
PostQuitMessage (0);
return 0;
}
return DefWindowProc (hwnd,message,wParam,lParam);
}
// **********
// CRaster::LoadBMPFile (FileName);
// - loads a BMP file into a CRaster object
// * supports non-RLE-compressed files of 1, 2, 4, 8 & 24 bits-per-pixel
int CRaster::LoadBMP (char * szFile)
{
BITMAPFILEHEADER bmfh;
BITMAPINFOHEADER bmih;
// Open file.
std::ifstream bmpfile (szFile , std::ios::in | std::ios::binary);
if (! bmpfile.is_open()) return 1; // Error opening file
// Load bitmap fileheader & infoheader
bmpfile.read ((char*)&bmfh,sizeof (BITMAPFILEHEADER));
bmpfile.read ((char*)&bmih,sizeof (BITMAPINFOHEADER));
// Check filetype signature
if (bmfh.bfType!='MB') return 2; // File is not BMP
// Assign some short variables:
BPP=bmih.biBitCount;
Width=bmih.biWidth;
Height= (bmih.biHeight>0) ? bmih.biHeight : -bmih.biHeight; // absoulte value
BytesPerRow = Width * BPP / 8;
BytesPerRow += (4-BytesPerRow%4) % 4; // int alignment
// If BPP aren't 24, load Palette:
if (BPP==24)
pbmi=(BITMAPINFO*)new char [sizeof(BITMAPINFO)];
else
{
pbmi=(BITMAPINFO*) new char[sizeof(BITMAPINFOHEADER)+(1<<BPP)*sizeof(RGBQUAD)];
//Palette=(RGBQUAD*)((char*)pbmi+sizeof(BITMAPINFOHEADER));
//bmpfile.read ((char*)Palette,sizeof (RGBQUAD) * (1<<BPP));
}
pbmi->bmiHeader=bmih;
// Load Raster
bmpfile.seekg (bmfh.bfOffBits, std::ios::beg);
Raster= new char[BytesPerRow*Height];
// (if height is positive the bmp is bottom-up, read it reversed)
if (bmih.biHeight>0)
for (int n=Height-1;n>=0;n--)
bmpfile.read (Raster+BytesPerRow*n,BytesPerRow);
else
bmpfile.read (Raster,BytesPerRow*Height);
// so, we always have a up-bottom raster (that is negative height for windows):
pbmi->bmiHeader.biHeight=-Height;
bmpfile.close();
return 0;
}
// **********
// CRaster::GDIPaint (hdc,x,y);
// * Paints Raster to a Windows DC.
int CRaster::GDIPaint (HDC hdc,int x=0,int y=0)
{
// Paint the image to the device.
return SetDIBitsToDevice (hdc,x,y, Width, Height, 0, 0, 0,Height,(LPVOID)Raster,pbmi,0);
}
If you all would take the time to pay attention to what I am asking rather than straying off, you will see that palette isn't used ever again. There are only 3 entries found of palette.
Those 2 lines commented out give either a black image or irregular colored, I really don't care which. Those 2 lines uncommented out give a nice clean correct picture. Those 2 lines shouldn't be getting applied to the image at all, from what I see....which goes back to those 2 lines being the only relevant lines. And I see this on a lot of examples, not just this one....whether you use a for loop to read in the palette or this way.
"Those 2 lines commented out" give you nothing but garbage that you then pass in SetDIBitsToDevice(...) function... :cool:Quote:
Originally Posted by zaryk
Really? I wouldn't ever guess. Have an Idea why they work when uncommented? Technically, they should give you garbage either way.
I don't know! Perhaps some correct data is read from a bitmap file?Quote:
Originally Posted by zaryk
Why does this surprise you? You're pointing "Palette" to the palette area of your bitmap, then reading the palette colors from the bmp file. Eliminating this step leaves random garbage in the palette area of your bitmap.Quote:
Originally Posted by zaryk
Victor: That might be an explanation, but still doesn't explain, why commented, the images are black or irregular colored, and uncommented it works perfect.
hox: Im surprised because its working and shouldn't be.
I don't see how this is applying the palette to anything.
Palette points to the palette area of the bitmapCode:if(!(bmp.palette = (RGBQUAD*) ((BYTE*)bmp.bitmapInfo + sizeof(BITMAPINFOHEADER))))
if(!fread(bmp.palette, sizeof(RGBQUAD), bmp.nColors, file))
retrieves the information
.....then what....never used in the final drawing of the image. Unless it automatically fills in bmp.bitmapInfo->bmiColors automatically?
How much clearer can I state it? There is a palette in the file and a palette in the bitmap structure. Commenting those lines makes the code fail to load the palette from the file. Without filling in the palette, there's random garbage in that part of the bitmap structure (or zeroed memory if you're in debug).
I guess I should have quoted since you edited your post eliminating all context of my reply. Apparently you understand now, right?
bmp.palette is being set to the bitmapinfo.bmiColors (the palette in the structure) address space, so when we read in the palette from the file, it reads into that address space and then because bitmapinfo is used to draw the image, it has everything needed? Just say yes, so we can leave.
Code:if(!(bmp.palette = (RGBQUAD*) ((BYTE*)bmp.bitmapInfo + sizeof(BITMAPINFOHEADER))))
if(!fread(bmp.palette, sizeof(RGBQUAD), bmp.nColors, file))
Yes.
To put it another way, you are passing pbmi to the SetDIBitsToDevice and pbmi contains a pointer to the palette, so it looks like the palette is being used by SetDIBitsToDevice.
Why someone like this gets any help at all after such temper tantrum outbursts is beyond me.
Zaryk needs help with programming....then insults the people trying to help.
Personally, even if I weren't offended by this ***, I wouldn't waste time trying to teach programming to someone who is so stupid that they insult the people they're asking for help from. Its like trying to teach an ape how to play piano--a waste of time.
Well, I could agree with you...Quote:
Originally Posted by Martin O
But perhaps, OP would be able (after so long discussion) to understand, that he was wrong with his attacks to the people trying to help him... :confused:
At least, it is what I hope... :rolleyes:
I doubt it. I remembered his name from a year or 2 ago. He pulled the same 'how dare you ask me to clarify myself, you must be stupid' BS then & still does it now. The stench of entitlement coming from him is overpowering. He's one of those simultaneously arrogant & incompetent individuals that I've seen too much of in IT. He's an extreme example of that.Quote:
Originally Posted by VictorN
Ok, Thanks for the info. :sick:Quote:
Originally Posted by Martin O
I'll keep it in mind...
Going by the previous posting history, the schtick is to ask a question with hardly any info, and then when simply asked for more info, insults are directed to the ones asking for more info.Quote:
Originally Posted by Martin O
One thread had to be shut down by Andreas because of this tactic.
Regards,
Paul McKenzie
Lucky for me, I don't feel bad for my outbursts. All it took to answer the question was the explanation of why those two lines worked, and everyone decided to go stupid, because most of the time they get people asking questions that require more detail. It could have been over in 1 reply, like most of my questions I have posted here. It's sad really.
I didn't gain anything from this, like most of my posts, except to pass the time while I was at work; I already had the answer when I asked. I like being argumentative and annoying. What makes all the much better, is that no one knows who I am. Plus, I have multiple personality disorder,....so I don't even know who I am. :D
I asked my 21 yr old brother, has a few years of experience, the same question, same detail, same 2 lines; and he answered on his 1st reply. But, then again, I understand why. Our father actually taught us to think before talking; use critical intelligence and observation; analyze everything.
I don't really care if you believe me or not. Honestly, I don't care if I get kicked off codeguru, there will always be someone to annoy as long as they let it get to them. Makes it fun, for me at least. :D Cheers.
I remember him mentioning this a few years ago--I don't think he's kidding. :eek:Quote:
Originally Posted by zaryk
Nice. Try this in a bar, or on the street, and see how long you last...Quote:
Originally Posted by zaryk
Viggy
That's the first post of yours which makes sense. I'll link to it the next time you ask a question. :wave:Quote:
Originally Posted by zaryk
I'm not an admin but IMHO, the posts like the last OP's one is a very good reason for ban...Quote:
Originally Posted by Zaccheus
I often wonder how many of the dumb questions we get are just trolls out for a laugh.
Very few I'd imagine - the OP is just making excuses for ignorance and frustration. When someone asks a question and is faced with a question of their own, he simply could not handle the idea that his knowledge was insufficient to process the nature of getting help requires effort, not just indolence.Quote:
Originally Posted by Zaccheus
A final note though - LET THIS THREAD DIE!
Believe what you want, but, in the future, think through my questions, and assume I am posting all relevant code, and I won't make trouble, otherwise your just going to have the same output. If I am not banned from codeguru, maybe in a year or two, or even few years from now, I'll post again to give you a chance to forget me (Why do you think I haven't posted in such a long time? It can't be because I felt bad from the last post I had on here or because I just stopped programming.); as I happily, move to other forums to continue my evil ways. muhahahaha :D. I'm out.
P.S. D@mn, I gave everything away. Poor me. :D