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Fix issue 185 (XOR highlight) :

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* Use a simple optimization algorithm to compute a good set of XOR color pairs
 * Algorothm is not very optimized (complexity is up to n^3). In practize, it stabilizes after 2 to 3 rounds of swapping colors
 * Use this color table for all XOR effects
 * Setting for grid color is now removed


git-svn-id: svn://pulkomandy.tk/GrafX2/trunk@2048 416bcca6-2ee7-4201-b75f-2eb2f807beb1
This commit is contained in:
Adrien Destugues
2013-01-06 12:46:46 +00:00
parent 65194af002
commit 878c926ce4
19 changed files with 173 additions and 175 deletions
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63
src/palette.c
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@@ -3010,66 +3010,3 @@ const T_Components * Favorite_GUI_color(byte color_index)
return &(Gfx->Default_palette[Gfx->Color[color_index]]);
}
byte xor_lut[256];
int Diff(int i, int j) {
// TODO try out different difference operators to see if the results get
// better (weight the components, use ² instead of abs, use HSL or XYZ or )
int diff = 0;
diff += abs(Main_palette[i].R - Main_palette[j].R);
diff += abs(Main_palette[i].G - Main_palette[j].G);
diff += abs(Main_palette[i].B - Main_palette[j].B);
return diff;
}
void compute_xor_table()
{
int i;
byte found;
// Initialize the table with some "random" values
for(i = 0; i < 256; i++)
{
xor_lut[i] = 255 - i;
}
do {
// Find the smallest difference in the table
int mindiff = INT_MAX;
int idx;
for(i = 0; i < 256; i++)
{
int diff = Diff(i, xor_lut[i]);
if (diff < mindiff) {
idx = i;
mindiff = diff;
}
}
// Try to pair these two colors better
found = 0;
for(i = 0; i < 256; i++)
{
// diffs before the swap
int before = Diff(idx, xor_lut[idx]) + Diff(i, xor_lut[i]);
// diffs after the swap
int after = Diff(idx, xor_lut[i]) + Diff(i, xor_lut[idx]);
if (after > before)
{
// Swapping these colors get us something "more different". Do it !
byte idx2 = xor_lut[i];
byte i2 = xor_lut[idx];
xor_lut[i] = i2;
xor_lut[i2] = i;
xor_lut[idx] = idx2;
xor_lut[idx2] = idx;
found = 1;
break;
}
}
} while(found);
}