Oh god, why do you hate whitespace so much, ProgrammerNerd? Here's a more consistent and readable version of your routine, with no major code changes (please see ProgrammerNerd's post for more details on using this):
Code: /* Note it is up to the caller to ensure that alpha is in range of 1-31.
* Also make sure width is a multiple of two.
*/
void CopySpriteMaskedAlpha(unsigned *data, unsigned x, unsigned y, unsigned width, unsigned height,
unsigned maskcolor, unsigned alpha)
{
unsigned short* v = (unsigned short*)0xa8000000;
unsigned* VRAM, w, alphai;
width >>= 1; // Most compilers know int/2 = int>>1; just making sure
v += 384 * y + x;
VRAM = v;
alphai = 32 - alpha;
// Note I have decided to do a minor tradeoff for speed.
// Make sure your alpha pixels are multiple of two*/
maskcolor |= maskcolor << 8;
// Note that this will not work for height=0 or width=0
while(height--) {
w = width;
while(w--) {
unsigned color1 = *data++;
if (color1 != maskcolor) {
// Note this is based on the source code of Fblend's function fblend_rect_trans_16
unsigned rbg_source, grb_source, temp1;
// Split up components to allow us to do operations
// on all of them at the same time
rbg_source = *VRAM & 0xF81F07E0,
grb_source = *VRAM & 0x07E0F81F;
// Multiply the source by the factor
rbg_source = ((rbg_source >> 5) * alpha) & 0xF81F07E0;
grb_source = ((grb_source * alpha) >> 5) & 0x07E0F81F;
// Split up RGB -> R-B and G
temp1 = color1 & 0x7E0F81F;
color1 &= 0xF81F07E0;
// Multiply the source by the factor
color1 = ((((color1 >> 5) * alphai) & 0xF81F07E0) + rbg_source) & 0xF81F07E0;
temp1 = ((((temp1 * alphai) >> 5) & 0x07E0F81F) + grb_source) & 0x07E0F81F;
color1 |= temp1;
*VRAM++ = color1;
} else {
++VRAM;
}
}
VRAM += (384/2) - width;
}
}
Sorry if it was a bit messy.
It is always good to know what others think of my code.
ProgrammerNerd wrote:
Sorry if it was a bit messy.
It is always good to know what others think of my code.
It's good code, certainly; I'm just increasingly picky about code style the more I work with others on C/C++ coding projects. 
To your credit (and Fblend's credit), I saw very little to optimize there that a decent compiler wouldn't catch anyway.
ProgrammerNerd, this is what I'm getting when I use your routine:
The mask color is 0xf800.
That was a minor bug in my code. I only bothered to test an image with a mask color of 0 hence me not noticing the bug.
Replace
Code:
maskcolor |= maskcolor << 8;
With
Code:
maskcolor |= maskcolor << 16;
Again, may I suggest using Bdisp_WriteGraphVRAM? Last time I checked it supported setting a mask color (that's how icons in the OS file manager are displayed) and a transparency level (presumably for things like fading g3p pictures on the background, but it works with any bitmap really). Tell me if you need help with it.
I have nothing against custom functions but I think you could save some binary space and possibly gain a little speed by using the syscall.
gbl08ma wrote:
Again, may I suggest using Bdisp_WriteGraphVRAM? Last time I checked it supported setting a mask color (that's how icons in the OS file manager are displayed) and a transparency level (presumably for things like fading g3p pictures on the background, but it works with any bitmap really). Tell me if you need help with it.
I have nothing against custom functions but I think you could save some binary space and possibly gain a little speed by using the syscall.
I would like help on this and was also trying to implement Optimization suggestions from http://prizm.cemetech.net/index.php/Display but must have messed up iterations as the sprites appeared double the size and could not shrink them - has anyone implemented the "unsigned int *" version successfully for like drawing black lines etc or anything more complex please?
ignore my comment about double the size - I somehow had the sprite of double the size by mistake to begin with - so will revisit unsigned int testing again when I have more time. Any help/examples of Bdisp_WriteGraphVRAM will be much appreciated from gbl08ma and all of you. Kind regards
Sorry about jumping to another question: Is there a system call to get a folder size please? Or any routine doing it efficiently if someone already had to deal with this before?
I was playing with Bfile_FindFirst/Next calls so far and only could retrieve sizes for files not folders and very oddly their _NON_SMEM versions are the calls I have success (for files not folders) with using \\\\fls0\\ prefix so any tips what I'm doing wrong will be greatly appreciated.
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