load state ability from command line

[libpicofe.git] / gp2x / cpuctrl.c

diff --git a/gp2x/cpuctrl.c b/gp2x/cpuctrl.c
index 9940fd5..b5b4736 100644 (file)
--- a/gp2x/cpuctrl.c
+++ b/gp2x/cpuctrl.c
@@ -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;
+       }
 }