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A_SN's curve

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git-svn-id: file:///home/notaz/opt/svn/PicoDrive@220 be3aeb3a-fb24-0410-a615-afba39da0efa
This commit is contained in:
notaz 2007-08-08 20:57:35 +00:00
parent 29a951879b
commit 82bc9cdd10
4 changed files with 39 additions and 18 deletions
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45
platform/gp2x/cpuctrl.c
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@ -255,25 +255,46 @@ void set_RAM_Timings(int tRC, int tRAS, int tWR, int tMRD, int tRFC, int tRP, in
}
void set_gamma(int g100)
void set_gamma(int g100, int A_SNs_curve)
{
float gamma = (float) g100 / 100;
int i;
//printf ("set gamma = %f\r\n",gamma);
gamma = 1/gamma;
//enable gamma
MEM_REG[0x2880>>1]&=~(1<<12);
//enable gamma
MEM_REG[0x2880>>1]&=~(1<<12);
MEM_REG[0x295C>>1]=0;
for(i=0; i<256; i++)
{
MEM_REG[0x295C>>1]=0;
for(i=0; i<256; i++)
{
unsigned char g;
unsigned short s;
g =(unsigned char)(255.0*pow(i/255.0,gamma));
s = (g<<8) | g;
unsigned short s;
const unsigned short grey50=143, grey75=177, grey25=97;
float blah;
if (A_SNs_curve)
{
// The next formula is all about gaussian interpolation
blah = (( -128 * exp(-powf((float) i/64.0f + 2.0f , 2.0f))) +
( -64 * exp(-powf((float) i/64.0f + 1.0f , 2.0f))) +
(grey25 * exp(-powf((float) i/64.0f - 1.0f , 2.0f))) +
(grey50 * exp(-powf((float) i/64.0f - 2.0f , 2.0f))) +
(grey75 * exp(-powf((float) i/64.0f - 3.0f , 2.0f))) +
( 256 * exp(-powf((float) i/64.0f - 4.0f , 2.0f))) +
( 320 * exp(-powf((float) i/64.0f - 5.0f , 2.0f))) +
( 384 * exp(-powf((float) i/64.0f - 6.0f , 2.0f)))) / (1.772637f);
blah += 0.5f;
}
else
{
blah = i;
}
g = (unsigned char)(255.0*pow(blah/255.0,gamma));
//printf("%d : %d\n", i, g);
s = (g<<8) | g;
MEM_REG[0x295E>>1]= s;
MEM_REG[0x295E>>1]= g;
}
MEM_REG[0x295E>>1]= g;
}
}