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//========================================================================
//
// SplashScreen.h
//
// Copyright 2003-2013 Glyph & Cog, LLC
//
//========================================================================
#ifndef SPLASHSCREEN_H
#define SPLASHSCREEN_H
#include <aconf.h>
#include "SplashTypes.h"
//------------------------------------------------------------------------
// SplashScreen
//------------------------------------------------------------------------
typedef Guchar *SplashScreenCursor;
class SplashScreen {
public:
SplashScreen(SplashScreenParams *params);
SplashScreen(SplashScreen *screen);
~SplashScreen();
SplashScreen *copy() { return new SplashScreen(this); }
// Return the computed pixel value (0=black, 1=white) for the gray
// level <value> at (<x>, <y>).
int test(int x, int y, Guchar value) {
int xx, yy;
xx = x & sizeM1;
yy = y & sizeM1;
return value < mat[(yy << log2Size) + xx] ? 0 : 1;
}
// To do a series of tests with the same y value, call
// getTestCursor(y), and then call testWithCursor(cursor, x, value)
// for each x.
SplashScreenCursor getTestCursor(int y) {
int yy;
yy = y & sizeM1;
return &mat[yy << log2Size];
}
int testWithCursor(SplashScreenCursor cursor, int x, Guchar value) {
int xx = x & sizeM1;
return value >= cursor[xx];
}
// Returns true if value is above the white threshold or below the
// black threshold, i.e., if the corresponding halftone will be
// solid white or black.
GBool isStatic(Guchar value) { return value < minVal || value >= maxVal; }
private:
void buildDispersedMatrix(int i, int j, int val,
int delta, int offset);
void buildClusteredMatrix();
int distance(int x0, int y0, int x1, int y1);
void buildSCDMatrix(int r);
Guchar *mat; // threshold matrix
int size; // size of the threshold matrix
int sizeM1; // size - 1
int log2Size; // log2(size)
Guchar minVal; // any pixel value below minVal generates
// solid black
Guchar maxVal; // any pixel value above maxVal generates
// solid white
};
#endif
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