Fastest way to erase a bitmap

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Sat, 2017-08-19 21:08

YesCop

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Last seen: 4 years 3 months ago

Joined: 2011-05-17 15:07

Fastest way to erase a bitmap

Hello there.
For AmigaOS4.1 last update.

I would want to find the best and fastest way to clear a (big like 1600x1050) bitmap.
For the moment I use BltClear from graphics library.
To use it I call LockBitmap before.

First, I have found that BltClear is not fast I supposed.
Second, it clears bitmap with 0. What could I do if I want to use a ARGB value?

Thanks for reading.

Sun, 2017-08-20 12:52

salass00

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Last seen: 6 months 1 week ago

Joined: 2011-02-03 11:27

Re: Fastest way to erase a bitmap

void ClearBitMapARGB(struct BitMap *bm, uint32 argb) {
    struct RastPort temp_rp;
    int32           width, height;
 
    width  = IGraphics->GetBitMapAttr(bm, BMA_WIDTH);
    height = IGraphics->GetBitMapAttr(bm, BMA_HEIGHT);
 
    IGraphics->InitRastPort(&temp_rp);
    temp_rp.BitMap = bm;
 
    IGraphics->RectFillColor(&temp_rp, 0, 0, width - 1, height - 1, argb);
}

Sat, 2017-09-09 13:13

YesCop

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Last seen: 4 years 3 months ago

Joined: 2011-05-17 15:07

Re: Fastest way to erase a bitmap

Thanks Salass.
I will test your solution as soon as possible.

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