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Problem drawing original non-Po2 image

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Problem drawing original non-Po2 image
« on: October 07, 2013, 11:58:43 »
Until a few days, i could draw without any problem images that originally were or not power of 2 size (wherever an image did not fullfill this requirement, i just resized its canvas and problem solved).

But i made some changes, and dont know why, when i draw an image that originally haven't a power of 2 size, it shows a rectangle with the expected size, but every pixel is the same as the bottom-left pixel of the image (so, if the image has in its corners a green pixel, it just displays a green rectangle).

I cant find the root of this issue. I think i did not change anything about how i load images from hard disk to memory. This is how i convert a bufferedimage to bytebuffer and how i send it to GPU:

Code: [Select]
public static int bindTexture(ByteBuffer buffer,int size){
buffer.flip();
glEnable(GL_TEXTURE_2D);
final int id = glGenTextures();
glBindTexture(GL_TEXTURE_2D, id);
glPixelStorei(GL_UNPACK_ALIGNMENT, 1);

glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_REPEAT);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_REPEAT);

glTexImage2D(GL_TEXTURE_2D,0,GL_RGBA,size,size,0,GL_RGBA,GL_UNSIGNED_BYTE,buffer);

return id;
}

public static ByteBuffer imageToBuffer(BufferedImage bufferedImage){
final int width = bufferedImage.getWidth();
final int height = bufferedImage.getHeight();
final ByteBuffer buffer = ByteBuffer.allocateDirect(width * height * 4);

for(int y=0;y<height;y++){
for(int x=0;x<width;x++){
final int argb = bufferedImage.getRGB(x, y);
final byte red   = (byte) ((argb >>> 16) & 0xFF);
final byte green = (byte) ((argb >>>  8) & 0xFF);
final byte blue  = (byte) ((argb >>>  0) & 0xFF);
final byte alpha = (byte) ((argb >>> 24) & 0xFF);

buffer.put(red).put(green).put(blue).put(alpha);
}
}

return buffer;
}

public static int getPowerOfTwo(int width, int height){
if(width+height<=2) return 2;
final int nw = Integer.highestOneBit(width-1)<<1;
        final int nh = Integer.highestOneBit(height-1)<<1;
        return Math.max(nw, nh);
}

public static BufferedImage resizeCanvas(BufferedImage buffer) {
        final int bW = buffer.getWidth();
        final int bH = buffer.getHeight();
        final int size = getPowerOfTwo(bW, bH);
       
        if (size+bW == size+bH) return buffer;
       
        final BufferedImage newImage = new BufferedImage(size,size,BufferedImage.TYPE_INT_ARGB);
        newImage.createGraphics().drawImage(buffer,null,0,0);
       
        return newImage;
    }

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Offline quew8

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Re: Problem drawing original non-Po2 image
« Reply #1 on: October 07, 2013, 16:33:39 »
To me, that sounds like a problem with your texture coords rather than the texture loading itself (I didn't notice any problems in the code you posted). I've had that problem so many times because I store the used texture size and the whole texture size as ints, so when I divide them without casting to a float I just get 0.

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Re: Problem drawing original non-Po2 image
« Reply #2 on: October 07, 2013, 16:45:26 »
To me, that sounds like a problem with your texture coords rather than the texture loading itself (I didn't notice any problems in the code you posted). I've had that problem so many times because I store the used texture size and the whole texture size as ints, so when I divide them without casting to a float I just get 0.

You were absolutely f*cking right. Thanks man, i swear if you didnt tell me this i would go mad.

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Offline quew8

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Re: Problem drawing original non-Po2 image
« Reply #3 on: October 07, 2013, 16:52:28 »
We've all been there. Glad I could help.