mandelbrot: only check bailout once every 2 iterations.

Once we bailed out we calculate the exact iteration in which it would have happened if needed.

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
This commit is contained in:
Michael Niedermayer 2011-11-13 18:14:40 +01:00
parent 41fd1b2d5a
commit 3cbe9afba5

View File

@ -186,7 +186,7 @@ static void draw_mandelbrot(AVFilterContext *ctx, uint32_t *color, int linesize,
double t;
if(zr*zr + zi*zi > mb->bailout){
switch(mb->outer){
case ITERATION_COUNT: zr= i; break;
case ITERATION_COUNT: zr = i - (SQR(zr-cr)+SQR(zi-ci) > SQR(mb->bailout)); break;
case NORMALIZED_ITERATION_COUNT: zr= i + log2(log(mb->bailout) / log(zr*zr + zi*zi)); break;
}
c= lrintf((sin(zr)+1)*127) + lrintf((sin(zr/1.234)+1)*127)*256*256 + lrintf((sin(zr/100)+1)*127)*256;
@ -199,14 +199,6 @@ static void draw_mandelbrot(AVFilterContext *ctx, uint32_t *color, int linesize,
mb->zyklus[i][1]= zi;
}
i++;
if(t*t + zi*zi > mb->bailout){
switch(mb->outer){
case ITERATION_COUNT: zr= i; break;
case NORMALIZED_ITERATION_COUNT: zr= i + log2(log(mb->bailout) / log(t*t + zi*zi)); break;
}
c= lrintf((sin(zr)+1)*127) + lrintf((sin(zr/1.234)+1)*127)*256*256 + lrintf((sin(zr/100)+1)*127)*256;
break;
}
zr= t*t - zi*zi+cr;
zi= 2*t*zi + ci;
if(use_zyklus){