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Mon, 17 Nov 2008 03:54:24 . . . . adsl196-109-51-217-196.adsl196-10.iam.net.ma

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= psetp =

== Syntax ==

:int psetp(int x, int y, int val)

== Arguments ==

:x, y

::Image coordinates


::Pixel value that shall be stored

== Return ==

:Always returns a value of 1

== Description ==

:This function lets you write a whole pixel to the output buffer. Using psetp instead of pset takes only approximately half as much time. You have to use the RGB or RGBA function to create a pixel value from individual color values. Make sure that the individual color values lie between 0 and 255, otherwise you will get a strange image effect when passing the pixel value to this function. For details please have a look at the example below. Currently only works with 8 bit images.

== Example ==




ctl(2): checkbox,"Use the faster srcp() and psetp()",size=(150,*),Val=0



int c,r,g,b;

int a=255;

const int startclock = clock();

int endclock;

for (y=y_start; y<y_end; y++){

if(updateProgress(y,y_end)) abort();

for (x=x_start; x<x_end; x++){

if (ctl(2)){

//Read a whole pixel

c = srcp (x,y);

//Explode it into the color values

r = Rval(c); //c & 0xff;

g = Gval(c); //c >> 8 & 0xff;

b = Bval(c); //c >> 16 & 0xff;

if (Z>3) a = Aval(c); //c >> 24 & 0xff;

//Adjust brightness

r += ctl(0);

g += ctl(0);

b += ctl(0);

if (Z>3) a += ctl(0);

//Makes sure that the color values are in the right range,

//otherwise we might get a strange image result

if (r<0) r=0; else if (r>255) r=255;

if (g<0) g=0; else if (g>255) g=255;

if (b<0) b=0; else if (b>255) b=255;

if (Z>3) {if (a<0) a=0; else if (a>255) a=255;}

//Write back the color values

psetp (x,y, RGBA(r,g,b,a) );

} else {

r = src(x,y,0);

g = src(x,y,1);

b = src(x,y,2);

if (Z>3) a = src(x,y,3);

r += ctl(0);

g += ctl(0);

b += ctl(0);

if (Z>3) a += ctl(0);

pset (x,y,0,r);

pset (x,y,1,g);

pset (x,y,2,b);

if (Z>3) pset (x,y,3,a);



endclock = clock() - startclock;

setCtlTextv(10, "Render time needed: %d ms", endclock);

//Display after applying the effect to the image

//Should make the speed difference more clear

if (!doingProxy) Info ("Render time needed: %d ms", endclock);

return true;



== Also see ==

:set_psetp_mode, srcp, pgetp, tgetp, tsetp, t2getp, t2setp, RGB, RGBA

== Comments ==

:Everyone can add his comments about his experiences with this function here. Tips for using it are welcome, too.