bmap_lock

bmap_lock(BMAP* bmap,var mode)

Preloads and locks a bitmap and returns its texture format. Mostly used for writing into or reading from a bitmap.

Parameters:

bmap	name or pointer of a bmap
mode	always 0

Returns:

0	invalid bitmap or unsupported format.
4	4 bit compressed DDS texture.
8	8 bit palettized texture.
88	16 bit UV texture, for effects or shaders.
565	16 bit RGB texture without alpha transparency.
888	24 bit RGB texture without alpha transparency.
1555	16 bit ARGB texture with 1 bit alpha, for sprites or overlays.
4444	16 bit ARGB texture with 4 bit alpha.
8888	32 bit ARGB texture with 8 bit alpha.
12	16 bit floating point format.
14	32 bit floating point format.
122	2x16 bit floating point format. A8
144	2x32 bit floating point format. A8
12222	4x16 bit floating point format. A7
14444	4x32 bit floating point format. A7

Speed:

Medium

Remarks:

The returned format depends on the use of the bitmap and its original image format. DDS images produce compressed textures, PCX and BMP images produce 16 bit textures and TGA images produce 24 or 32 bit textures. Pixel instructions only work with ARGB format 565 or above.
Render target bitmaps must be converted through bmap_to_format before they can be locked.
A bitmap must be unlocked for being visible on the screen.
After locking an uncompressed bitmap, you can access its texture content directly through the bmap.finalbits pointer. The texture size (in bytes) is given through (mybmap.finalwidth * mybmap.finalheight * bmap.finalbytespp). The texture size is normally a power of 2 and not identical to the original image size returned by bmap_width and bmap_height.
Bitmap content can not be accessed on a stand-alone server, or before the first frame when the DirectX device is not yet opened.

Example:

 // paint a red cross into a bmap
var format; 
var pixel;
format = bmap_lock(tgablitz,0);
if (format >= 565) {
     pixel = pixel_for_vec(vector(0,0,255),100,format); // red color
     pixel_to_bmap(tgablitz,10,10,pixel);
     pixel_to_bmap(tgablitz,10,11,pixel);
     pixel_to_bmap(tgablitz,10,12,pixel);
     pixel_to_bmap(tgablitz,10,13,pixel);
     pixel_to_bmap(tgablitz,10,14,pixel);
     pixel_to_bmap(tgablitz,8,12,pixel);
     pixel_to_bmap(tgablitz,9,12,pixel);
     pixel_to_bmap(tgablitz,11,12,pixel);
     pixel_to_bmap(tgablitz,12,12,pixel);
}
bmap_unlock(tgablitz); // unlock the locked bitmap

bmap_lock(BMAP* bmap,var mode)

Parameters:

Returns:

Speed:

Remarks:

Example:

See also: