#define __NR_PIXBLOCK_SCALER_CPP__

#include <glib.h>

#include <cmath>

#include "round.h"

using Inkscape::round;

using std::floor;

#include "libnr/nr-pixblock.h"

#include "libnr/nr-matrix.h"

namespace NR {

struct RGBA {

int r, g, b, a;

};

inline void _check_index(NRPixBlock const * const pb, int const location, int const line)

{

if(false) {

int max_loc = pb->rs * (pb->area.y1 - pb->area.y0);

if (location < 0 || (location + 4) > max_loc)

g_warning("Location %d out of bounds (0 ... %d) at line %d", location, max_loc, line);

}

}

void transform_nearest(NRPixBlock *to, NRPixBlock *from, Matrix &trans)

{

if (NR_PIXBLOCK_BPP(from) != 4 || NR_PIXBLOCK_BPP(to) != 4) {

g_warning("A non-32-bpp image passed to transform_nearest: scaling aborted.");

return;

}

// Precalculate sizes of source and destination pixblocks

int from_width = from->area.x1 - from->area.x0;

int from_height = from->area.y1 - from->area.y0;

int to_width = to->area.x1 - to->area.x0;

int to_height = to->area.y1 - to->area.y0;

Matrix itrans = trans.inverse();

// Loop through every pixel of destination image, a line at a time

for (int to_y = 0 ; to_y < to_height ; to_y++) {

for (int to_x = 0 ; to_x < to_width ; to_x++) {

RGBA result = {0,0,0,0};

int from_x = (int)round(itrans[0] * (to_x + to->area.x0)

+ itrans[2] * (to_y + to->area.y0)

+ itrans[4]);

from_x -= from->area.x0;

int from_y = (int)round(itrans[1] * (to_x + to->area.x0)

+ itrans[3] * (to_y + to->area.y0)

+ itrans[5]);

from_y -= from->area.y0;

if (from_x >= 0 && from_x < from_width

&& from_y >= 0 && from_y < from_height) {

_check_index(from, from_y * from->rs + from_x * 4, __LINE__);

result.r = NR_PIXBLOCK_PX(from)[from_y * from->rs + from_x * 4];

result.g = NR_PIXBLOCK_PX(from)[from_y * from->rs + from_x * 4 + 1];

result.b = NR_PIXBLOCK_PX(from)[from_y * from->rs + from_x * 4 + 2];

result.a = NR_PIXBLOCK_PX(from)[from_y * from->rs + from_x * 4 + 3];

}

_check_index(to, to_y * to->rs + to_x * 4, __LINE__);

NR_PIXBLOCK_PX(to)[to_y * to->rs + to_x * 4] = result.r;

NR_PIXBLOCK_PX(to)[to_y * to->rs + to_x * 4 + 1] = result.g;

NR_PIXBLOCK_PX(to)[to_y * to->rs + to_x * 4 + 2] = result.b;

NR_PIXBLOCK_PX(to)[to_y * to->rs + to_x * 4 + 3] = result.a;

}

}

}

} /* namespace NR */