Hi I have a problem with my memblock. It's not taking out all the colors for see through

Author

Message

darkvee

20

Years of Service

User Offline

Joined: 18th Nov 2005

Location:

Posted: 12th Oct 2012 19:19 Edited at: 12th Oct 2012 19:20

Link

Hi I'm having a problem taking out all of the color values of rgb(255,0,255) in the memblock. I want to get rid of any color value that matches that and make it see through.

Here is the code that shows it. Notice on the rabbit I still have 255,0,255 color pixels in it.

I'm going to upload the rabbit image i'm using.

Anyone know how to take all that 255,0,255 out?

color backdrop 0,rgb(0,0,0)
//set image colorkey 255,0,255
load image "cool.png",1

// make memblock from image
make memblock from image 1,1

// get memblock image values
screenWidth = memblock dword(1,0)
screenHeight = memblock dword(1,4)
bytes = memblock dword(1,8)/8

// loop through the memblock and take out the color 255,0,255
for row = 0 to screenHeight-1
    for col = 0 to screenWidth-1
    
        // make sure it gets x,y of screen
        post = col*bytes + row*bytes*screenWidth
        
        // get the color data from the memblock
        currentvalueB = memblock byte(1,post)
        currentvalueG = memblock byte(1,post+1)
        currentvalueR = memblock byte(1,post+2)
        currentvalueA = memblock byte(1,post+3)
        
        // see if the color matches 255,0,255
        // if it does make that see through
        if currentvalueR = 255 and currentvalueG = 0 and currentvalueB = 255 and currentvalueA > 0
            // set the values to see through
            currentvalueR = 0
            currentvalueG = 0
            currentvalueB = 0
            currentvalueA = 0
            
            //write the values to update it
            write memblock byte 1, post, currentvalueB
            write memblock byte 1, post+1, currentvalueG
            write memblock byte 1, post+2, currentvalueR
            write memblock byte 1, post+3, currentvalueA
            
        endif
    
   
    next col
next row

// make a object
make object cube 1,10

// delete the image before we apply the update from the memblock
delete image 1

// now update the image from memblock
make image from memblock 1,1

// put it on sprite to see the results
sprite 1,100,0,1
set sprite 1,0,1

//update
sync
wait key
delete memblock 1
end

+ Code Snippet


color backdrop 0,rgb(0,0,0)
//set image colorkey 255,0,255
load image "cool.png",1

// make memblock from image
make memblock from image 1,1

// get memblock image values
screenWidth = memblock dword(1,0)
screenHeight = memblock dword(1,4)
bytes = memblock dword(1,8)/8

// loop through the memblock and take out the color 255,0,255
for row = 0 to screenHeight-1
    for col = 0 to screenWidth-1
    
        // make sure it gets x,y of screen
        post = col*bytes + row*bytes*screenWidth
        
        // get the color data from the memblock
        currentvalueB = memblock byte(1,post)
        currentvalueG = memblock byte(1,post+1)
        currentvalueR = memblock byte(1,post+2)
        currentvalueA = memblock byte(1,post+3)
        
        // see if the color matches 255,0,255
        // if it does make that see through
        if currentvalueR = 255 and currentvalueG = 0 and currentvalueB = 255 and currentvalueA > 0
            // set the values to see through
            currentvalueR = 0
            currentvalueG = 0
            currentvalueB = 0
            currentvalueA = 0
            
            //write the values to update it
            write memblock byte 1, post, currentvalueB
            write memblock byte 1, post+1, currentvalueG
            write memblock byte 1, post+2, currentvalueR
            write memblock byte 1, post+3, currentvalueA
            
        endif
    
   
    next col
next row


// make a object
make object cube 1,10

// delete the image before we apply the update from the memblock
delete image 1

// now update the image from memblock
make image from memblock 1,1

// put it on sprite to see the results
sprite 1,100,0,1
set sprite 1,0,1

//update
sync
wait key
delete memblock 1
end

darkvee

Back to top

Profile PM Email

paul5147

20

Years of Service

User Offline

Joined: 11th Jan 2006

Location: Hot & Sunny

Posted: 12th Oct 2012 19:54

Link

Dont really see much wrong with this code,try this and see if its what you were expecting,the image is definitely transparent as the cube shows once the texture is applied.

`Main Source File

`*********************************
`enviroment set up

IF CHECK DISPLAY MODE(1024,768,32) 
	SET DISPLAY MODE 1024,768,32
	h=DESKTOP HEIGHT()
	w=DESKTOP WIDTH()
	posx=w/2-512
	posy=h/2-384
ELSE
	SET DISPLAY MODE 640,480,32
	h=DESKTOP HEIGHT()
	w=DESKTOP WIDTH()
	posx=w/2-320
	posy=h/2-240
ENDIF
SET WINDOW POSITION posx,posy

SYNC ON
SYNC RATE 60
AUTOCAM OFF
HIDE MOUSE
COLOR BACKDROP 0,rgb(125,125,255)
SET TEXT FONT "Arial"
SET TEXT SIZE 12
SET TEXT TRANSPARENT

POSITION CAMERA 50,50,-50
POINT CAMERA 0,0,0
POSITION MOUSE SCREEN WIDTH()/2,SCREEN HEIGHT()/2
dummy=MOUSEMOVEX()
dummy=MOUSEMOVEY()

`*********************************	
`declarations and setup starts here
load image "cool.png",1

// make memblock from image
make memblock from image 1,1

// get memblock image values
screenWidth = memblock dword(1,0)
screenHeight = memblock dword(1,4)
bytes = memblock dword(1,8)/8

// loop through the memblock and take out the color 255,0,255
for row = 0 to screenHeight-1
    for col = 0 to screenWidth-1
    
        // make sure it gets x,y of screen
        post = col*bytes + row*bytes*screenWidth
        
        // get the color data from the memblock
        currentvalueB = memblock byte(1,post)
        currentvalueG = memblock byte(1,post+1)
        currentvalueR = memblock byte(1,post+2)
        currentvalueA = memblock byte(1,post+3)
        
        // see if the color matches 255,0,255
        // if it does make that see through
        if currentvalueR = 255 and currentvalueG = 0 and currentvalueB = 255 and currentvalueA > 0
            // set the values to see through
            currentvalueR = 0
            currentvalueG = 0
            currentvalueB = 0
            currentvalueA = 0
            
            //write the values to update it
            write memblock byte 1, post, currentvalueB
            write memblock byte 1, post+1, currentvalueG
            write memblock byte 1, post+2, currentvalueR
            write memblock byte 1, post+3, currentvalueA
            
        endif
    
   
    next col
next row

// delete the image before we apply the update from the memblock
delete image 1

// now update the image from memblock
make image from memblock 1,1
// make a object
make object cube 1,10
TEXTURE OBJECT 1,1
SET OBJECT TRANSPArency 1,2

`*********************************
`main loop starts here
DO
	
	mouse_control(1.0)
	SYNC
LOOP

`*********************************
`functions start here
FUNCTION mouse_control(speed AS FLOAT)
	XROTATE CAMERA CAMERA ANGLE X()+MOUSEMOVEY()
	YROTATE CAMERA CAMERA ANGLE Y()+MOUSEMOVEX()
	IF MOUSECLICK()=1 THEN MOVE CAMERA speed
	IF MOUSECLICK()=2 THEN MOVE CAMERA (0-speed)
	dummy=MOUSEMOVEX()
	dummy=MOUSEMOVEY()
ENDFUNCTION

+ Code Snippet

`Main Source File

`*********************************
`enviroment set up

IF CHECK DISPLAY MODE(1024,768,32) 
	SET DISPLAY MODE 1024,768,32
	h=DESKTOP HEIGHT()
	w=DESKTOP WIDTH()
	posx=w/2-512
	posy=h/2-384
ELSE
	SET DISPLAY MODE 640,480,32
	h=DESKTOP HEIGHT()
	w=DESKTOP WIDTH()
	posx=w/2-320
	posy=h/2-240
ENDIF
SET WINDOW POSITION posx,posy

SYNC ON
SYNC RATE 60
AUTOCAM OFF
HIDE MOUSE
COLOR BACKDROP 0,rgb(125,125,255)
SET TEXT FONT "Arial"
SET TEXT SIZE 12
SET TEXT TRANSPARENT

POSITION CAMERA 50,50,-50
POINT CAMERA 0,0,0
POSITION MOUSE SCREEN WIDTH()/2,SCREEN HEIGHT()/2
dummy=MOUSEMOVEX()
dummy=MOUSEMOVEY()

`*********************************	
`declarations and setup starts here
load image "cool.png",1

// make memblock from image
make memblock from image 1,1

// get memblock image values
screenWidth = memblock dword(1,0)
screenHeight = memblock dword(1,4)
bytes = memblock dword(1,8)/8

// loop through the memblock and take out the color 255,0,255
for row = 0 to screenHeight-1
    for col = 0 to screenWidth-1
    
        // make sure it gets x,y of screen
        post = col*bytes + row*bytes*screenWidth
        
        // get the color data from the memblock
        currentvalueB = memblock byte(1,post)
        currentvalueG = memblock byte(1,post+1)
        currentvalueR = memblock byte(1,post+2)
        currentvalueA = memblock byte(1,post+3)
        
        // see if the color matches 255,0,255
        // if it does make that see through
        if currentvalueR = 255 and currentvalueG = 0 and currentvalueB = 255 and currentvalueA > 0
            // set the values to see through
            currentvalueR = 0
            currentvalueG = 0
            currentvalueB = 0
            currentvalueA = 0
            
            //write the values to update it
            write memblock byte 1, post, currentvalueB
            write memblock byte 1, post+1, currentvalueG
            write memblock byte 1, post+2, currentvalueR
            write memblock byte 1, post+3, currentvalueA
            
        endif
    
   
    next col
next row



// delete the image before we apply the update from the memblock
delete image 1

// now update the image from memblock
make image from memblock 1,1
// make a object
make object cube 1,10
TEXTURE OBJECT 1,1
SET OBJECT TRANSPArency 1,2


`*********************************
`main loop starts here
DO
	
	mouse_control(1.0)
	SYNC
LOOP

`*********************************
`functions start here
FUNCTION mouse_control(speed AS FLOAT)
	XROTATE CAMERA CAMERA ANGLE X()+MOUSEMOVEY()
	YROTATE CAMERA CAMERA ANGLE Y()+MOUSEMOVEX()
	IF MOUSECLICK()=1 THEN MOVE CAMERA speed
	IF MOUSECLICK()=2 THEN MOVE CAMERA (0-speed)
	dummy=MOUSEMOVEX()
	dummy=MOUSEMOVEY()
ENDFUNCTION

Back to top

Profile PM

darkvee

20

Years of Service

User Offline

Joined: 18th Nov 2005

Location:

Posted: 12th Oct 2012 20:08

Link

Hi paul,

I still see the color Magenta rgb(255,0,255) When I zoom in. but thanks for the help though

darkvee

Back to top

Profile PM Email

Scraggle

Moderator

23

Years of Service

User Offline

Joined: 10th Jul 2003

Location: Yorkshire

Posted: 13th Oct 2012 11:50 Edited at: 13th Oct 2012 11:53

Link

Your code is sound. From that you will be removing all of the 'pure' magenta. What you are probably seeing is the pixels that are close to but not magenta caused by anti-aliasing in the initial image creation.

If you made the image, then I would suggest making it again but turn off anti-aliasing. Or better still, make it with a transparent background.

If you really must use this image then instead of removing the pure magenta, remove everything that isn't pure green. It may give you hard edges though, so perhaps create your own anti-aliasing by setting the transparency level of the pixels depending on how far off the pure colour they are.

The edge of your image - not pure green/pure magenta:

Back to top

Profile PM Email

darkvee

20

Years of Service

User Offline

Joined: 18th Nov 2005

Location:

Posted: 16th Oct 2012 15:55 Edited at: 16th Oct 2012 15:56

Link

Hi Scraggle,

Thanks man.

So I need to also make it anti-aliasing for it to work.

I'm thinking after I take out all the magenta. Use another function that goes around it and adds a same pixels for up,down,left,right. This should solve the problem.

darkvee

Back to top

Profile PM Email

Scraggle

Moderator

23

Years of Service

User Offline

Joined: 10th Jul 2003

Location: Yorkshire

Posted: 16th Oct 2012 19:21

Link

Quote: "Use another function that goes around it and adds a same pixels for up,down,left,right."

That sounds like a lot of effort when you could achieve the same thing by doing what I suggested:

Quote: "remove everything that isn't pure green"

Back to top

Profile PM Email

The Weeping Corpse

14

Years of Service

User Offline

Joined: 19th Sep 2011

Location: United Kingdom

Posted: 16th Oct 2012 19:50

Link

A few years ago I was working with green screens. Searching for and removing pure green pixels is a bad idea, you need to implement some kind of tolerance or do as Scraggle suggested, remove everything that isnt pure green.

www.youtube.com/user/TheWeepingCorpse

www.theweepingcorpse.com

Back to top

Profile PM Email

Phaelax

DBPro Master

23

Years of Service

User Offline

Joined: 16th Apr 2003

Location: Metropia

Posted: 16th Oct 2012 20:10 Edited at: 16th Oct 2012 20:12

Link

As scraggle suggested, remove anything that isn't pure green. All you have to change to your existing code is this:

+ Code Snippet

if (currentvalueR <> 0 and currentvalueG <> 255 and currentvalueB <> 30)

Might get rough edges, but all the magenta will be gone. Also noticed your "green" is really rgb(0,255,30).

But, if you really want the edges to have AA and simply remove that slight bit of magenta from it, then we could do that too!

I'll state that this method only works as simply as it does here because only two solid colors are involved in the overall makeup of the image, and we know what those two colors are.

Using linear interpolation, determine the amount the green has faded into the magenta to result in the particular color we see. For pure magenta, green has faded completely so we replace those pixels with green with an alpha value of 0. As for the edges, some green will be there resulting in values between 0 and 1. Replace those edge pixels with solid green and adjust their alpha accordingly.

Try this.

Rem Project: Dark Basic Pro Project
Rem Created: Tuesday, October 16, 2012

Rem ***** Main Source File *****

color backdrop 0,rgb(0,0,0)
//set image colorkey 255,0,255
load image "d:\cool.png",1

// make memblock from image
make memblock from image 1,1

// get memblock image values
screenWidth = memblock dword(1,0)
screenHeight = memblock dword(1,4)
bytes = memblock dword(1,8)/8

// loop through the memblock and take out the color 255,0,255
for row = 0 to screenHeight-1
    for col = 0 to screenWidth-1
    
        // make sure it gets x,y of screen
        post = col*bytes + row*bytes*screenWidth
        
        // get the color data from the memblock
        currentvalueB = memblock byte(1,post)
        currentvalueG = memblock byte(1,post+1)
        currentvalueR = memblock byte(1,post+2)
        currentvalueA = memblock byte(1,post+3)
        color = rgb(currentvalueR, currentvalueG, currentvalueB)
        
        rem If color is anything but green (in this case rgb[0,255,30] is green)
        if (currentvalueR <> 0 and currentvalueG <> 255 and currentvalueB <> 30)
            
            i# = 1.0 - (255.0 - currentvalueG) / -(0-255.0)
            
            currentvalueR = 0
            currentvalueG = 255
            currentvalueB = 30
            currentvalueA = 255*i#
            
            
            //write the values to update it
            write memblock byte 1, post, currentvalueB
            write memblock byte 1, post+1, currentvalueG
            write memblock byte 1, post+2, currentvalueR
            write memblock byte 1, post+3, currentvalueA
            
        endif
        
   
    next col
next row

// make a object
make object cube 1,10

// delete the image before we apply the update from the memblock
delete image 1

// now update the image from memblock
make image from memblock 1,1

// put it on sprite to see the results
sprite 1,100,0,1
set sprite 1,0,1

//update
sync
wait key
delete memblock 1
end

+ Code Snippet

Rem Project: Dark Basic Pro Project
Rem Created: Tuesday, October 16, 2012

Rem ***** Main Source File *****

color backdrop 0,rgb(0,0,0)
//set image colorkey 255,0,255
load image "d:\cool.png",1

// make memblock from image
make memblock from image 1,1

// get memblock image values
screenWidth = memblock dword(1,0)
screenHeight = memblock dword(1,4)
bytes = memblock dword(1,8)/8


// loop through the memblock and take out the color 255,0,255
for row = 0 to screenHeight-1
    for col = 0 to screenWidth-1
    
        // make sure it gets x,y of screen
        post = col*bytes + row*bytes*screenWidth
        
        // get the color data from the memblock
        currentvalueB = memblock byte(1,post)
        currentvalueG = memblock byte(1,post+1)
        currentvalueR = memblock byte(1,post+2)
        currentvalueA = memblock byte(1,post+3)
        color = rgb(currentvalueR, currentvalueG, currentvalueB)
        
        rem If color is anything but green (in this case rgb[0,255,30] is green)
        if (currentvalueR <> 0 and currentvalueG <> 255 and currentvalueB <> 30)
            
            i# = 1.0 - (255.0 - currentvalueG) / -(0-255.0)
            
            currentvalueR = 0
            currentvalueG = 255
            currentvalueB = 30
            currentvalueA = 255*i#
            
            
            //write the values to update it
            write memblock byte 1, post, currentvalueB
            write memblock byte 1, post+1, currentvalueG
            write memblock byte 1, post+2, currentvalueR
            write memblock byte 1, post+3, currentvalueA
            
        endif
        
   
    next col
next row


// make a object
make object cube 1,10

// delete the image before we apply the update from the memblock
delete image 1

// now update the image from memblock
make image from memblock 1,1

// put it on sprite to see the results
sprite 1,100,0,1
set sprite 1,0,1

//update
sync
wait key
delete memblock 1
end

"You're not going crazy. You're going sane in a crazy world!" ~Tick

Back to top

Profile PM Email Website

The Weeping Corpse

14

Years of Service

User Offline

Joined: 19th Sep 2011

Location: United Kingdom

Posted: 16th Oct 2012 21:15

Link

I don't want to go off on a tangent but this is an optimized version of Phaelax's code (just the for loops)

for row = 0 to screenHeight-1
    // calc base address of this row
    rowbase = row*bytes*screenwidth

for col = 0 to screenWidth-1
    
        // make sure it gets x,y of screen
        post = rowbase + (col*bytes)
        
        // get the color data from the memblock
        currentvalueB = memblock byte(1,post)
        if currentvalueB <> 30  
            currentvalueG = memblock byte(1,post+1)
            if currentvalueG <> 255
                currentvalueR = memblock byte(1,post+2)
                if currentvalueR <> 0
                  currentvalueA = memblock byte(1,post+3)
                  color = rgb(currentvalueR, currentvalueG, currentvalueB)
        
                  // if we get here then color is anything but green (in this case rgb[0,255,30] is green)
            
                  i# = 1.0 - (255.0 - currentvalueG) / -(0-255.0)
            
                  currentvalueR = 0
                  currentvalueG = 255
                  currentvalueB = 30
                  currentvalueA = 255*i#
            
            
                  //write the values to update it
                  write memblock byte 1, post, currentvalueB
                  write memblock byte 1, post+1, currentvalueG
                  write memblock byte 1, post+2, currentvalueR
                  write memblock byte 1, post+3, currentvalueA
              endif
            endif    
        endif
    next col
next row

+ Code Snippet

for row = 0 to screenHeight-1
    // calc base address of this row
    rowbase = row*bytes*screenwidth

    for col = 0 to screenWidth-1
    
        // make sure it gets x,y of screen
        post = rowbase + (col*bytes)
        
        // get the color data from the memblock
        currentvalueB = memblock byte(1,post)
        if currentvalueB <> 30  
            currentvalueG = memblock byte(1,post+1)
            if currentvalueG <> 255
                currentvalueR = memblock byte(1,post+2)
                if currentvalueR <> 0
                  currentvalueA = memblock byte(1,post+3)
                  color = rgb(currentvalueR, currentvalueG, currentvalueB)
        
                  // if we get here then color is anything but green (in this case rgb[0,255,30] is green)
            
                  i# = 1.0 - (255.0 - currentvalueG) / -(0-255.0)
            
                  currentvalueR = 0
                  currentvalueG = 255
                  currentvalueB = 30
                  currentvalueA = 255*i#
            
            
                  //write the values to update it
                  write memblock byte 1, post, currentvalueB
                  write memblock byte 1, post+1, currentvalueG
                  write memblock byte 1, post+2, currentvalueR
                  write memblock byte 1, post+3, currentvalueA
              endif
            endif    
        endif
    next col
next row

www.youtube.com/user/TheWeepingCorpse

www.theweepingcorpse.com

Back to top

Profile PM Email

darkvee

20

Years of Service

User Offline

Joined: 18th Nov 2005

Location:

Posted: 17th Oct 2012 15:27

Link

Hi Phaelax,

Thanks helping me out.

Hi The Weeping Corpse, so that is faster as in looping. I wasn't worried about speed right now but thanks for the tip.

darkvee

Back to top

Profile PM Email

Mage

Valued Member

19

Years of Service

User Offline

Joined: 3rd Feb 2007

Location:

Posted: 20th Oct 2012 19:42

Link

I think someone should ask, Why are you using a Color Key to achieve transparency instead of using Alpha level opacity?

Why not simply save an image as being partially transparent in the first place?

I think answering this question might allow people to give you a fundamentally better approach if it exists.

Back to top

Profile PM

Sorry your browser is not supported!

DarkBASIC Professional Discussion / Hi I have a problem with my memblock. It's not taking out all the colors for see through