You cannot select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
405 lines
9.0 KiB
C++
405 lines
9.0 KiB
C++
// This code is in the public domain -- castanyo@yahoo.es
|
|
|
|
#include <nvmath/Box.h>
|
|
#include <nvimage/ColorBlock.h>
|
|
#include <nvimage/Image.h>
|
|
|
|
using namespace nv;
|
|
|
|
namespace {
|
|
|
|
// Get approximate luminance.
|
|
inline static uint colorLuminance(Color32 c)
|
|
{
|
|
return c.r + c.g + c.b;
|
|
}
|
|
|
|
// Get the euclidean distance between the given colors.
|
|
inline static uint colorDistance(Color32 c0, Color32 c1)
|
|
{
|
|
return (c0.r - c1.r) * (c0.r - c1.r) + (c0.g - c1.g) * (c0.g - c1.g) + (c0.b - c1.b) * (c0.b - c1.b);
|
|
}
|
|
|
|
} // namespace`
|
|
|
|
|
|
/// Default constructor.
|
|
ColorBlock::ColorBlock()
|
|
{
|
|
}
|
|
|
|
/// Init the color block from an array of colors.
|
|
ColorBlock::ColorBlock(const uint * linearImage)
|
|
{
|
|
for(uint i = 0; i < 16; i++) {
|
|
color(i) = Color32(linearImage[i]);
|
|
}
|
|
}
|
|
|
|
/// Init the color block with the contents of the given block.
|
|
ColorBlock::ColorBlock(const ColorBlock & block)
|
|
{
|
|
for(uint i = 0; i < 16; i++) {
|
|
color(i) = block.color(i);
|
|
}
|
|
}
|
|
|
|
|
|
/// Initialize this color block.
|
|
ColorBlock::ColorBlock(const Image * img, uint x, uint y)
|
|
{
|
|
init(img, x, y);
|
|
}
|
|
|
|
void ColorBlock::init(const Image * img, uint x, uint y)
|
|
{
|
|
nvDebugCheck(img != NULL);
|
|
|
|
const uint bw = min(img->width() - x, 4U);
|
|
const uint bh = min(img->height() - y, 4U);
|
|
|
|
nvDebugCheck(bw != 0);
|
|
nvDebugCheck(bh != 0);
|
|
|
|
static int remainder[] = {
|
|
0, 0, 0, 0,
|
|
0, 1, 0, 1,
|
|
0, 1, 2, 0,
|
|
0, 1, 2, 3,
|
|
};
|
|
|
|
// Blocks that are smaller than 4x4 are handled by repeating the pixels.
|
|
// @@ Thats only correct when block size is 1, 2 or 4, but not with 3. :(
|
|
|
|
for(uint i = 0; i < 4; i++) {
|
|
//const int by = i % bh;
|
|
const int by = remainder[(bh - 1) * 4 + i];
|
|
for(uint e = 0; e < 4; e++) {
|
|
//const int bx = e % bw;
|
|
const int bx = remainder[(bw - 1) * 4 + e];
|
|
color(e, i) = img->pixel(x + bx, y + by);
|
|
}
|
|
}
|
|
}
|
|
|
|
|
|
void ColorBlock::swizzleDXT5n()
|
|
{
|
|
for(int i = 0; i < 16; i++)
|
|
{
|
|
Color32 c = m_color[i];
|
|
m_color[i] = Color32(0xFF, c.g, 0, c.r);
|
|
}
|
|
}
|
|
|
|
void ColorBlock::splatX()
|
|
{
|
|
for(int i = 0; i < 16; i++)
|
|
{
|
|
uint8 x = m_color[i].r;
|
|
m_color[i] = Color32(x, x, x, x);
|
|
}
|
|
}
|
|
|
|
void ColorBlock::splatY()
|
|
{
|
|
for(int i = 0; i < 16; i++)
|
|
{
|
|
uint8 y = m_color[i].g;
|
|
m_color[i] = Color32(y, y, y, y);
|
|
}
|
|
}
|
|
|
|
/// Returns true if the block has a single color.
|
|
bool ColorBlock::isSingleColor() const
|
|
{
|
|
Color32 mask(0xFF, 0xFF, 0xFF, 0x00);
|
|
uint u = m_color[0].u & mask.u;
|
|
|
|
for (int i = 1; i < 16; i++)
|
|
{
|
|
if (u != (m_color[i].u & mask.u))
|
|
{
|
|
return false;
|
|
}
|
|
}
|
|
|
|
return true;
|
|
}
|
|
|
|
/// Count number of unique colors in this color block.
|
|
uint ColorBlock::countUniqueColors() const
|
|
{
|
|
uint count = 0;
|
|
|
|
// @@ This does not have to be o(n^2)
|
|
for(int i = 0; i < 16; i++)
|
|
{
|
|
bool unique = true;
|
|
for(int j = 0; j < i; j++) {
|
|
if( m_color[i] != m_color[j] ) {
|
|
unique = false;
|
|
}
|
|
}
|
|
|
|
if( unique ) {
|
|
count++;
|
|
}
|
|
}
|
|
|
|
return count;
|
|
}
|
|
|
|
/// Get average color of the block.
|
|
Color32 ColorBlock::averageColor() const
|
|
{
|
|
uint r, g, b, a;
|
|
r = g = b = a = 0;
|
|
|
|
for(uint i = 0; i < 16; i++) {
|
|
r += m_color[i].r;
|
|
g += m_color[i].g;
|
|
b += m_color[i].b;
|
|
a += m_color[i].a;
|
|
}
|
|
|
|
return Color32(uint8(r / 16), uint8(g / 16), uint8(b / 16), uint8(a / 16));
|
|
}
|
|
|
|
/// Return true if the block is not fully opaque.
|
|
bool ColorBlock::hasAlpha() const
|
|
{
|
|
for (uint i = 0; i < 16; i++)
|
|
{
|
|
if (m_color[i].a != 255) return true;
|
|
}
|
|
return false;
|
|
}
|
|
|
|
|
|
/// Get diameter color range.
|
|
void ColorBlock::diameterRange(Color32 * start, Color32 * end) const
|
|
{
|
|
nvDebugCheck(start != NULL);
|
|
nvDebugCheck(end != NULL);
|
|
|
|
Color32 c0, c1;
|
|
uint best_dist = 0;
|
|
|
|
for(int i = 0; i < 16; i++) {
|
|
for (int j = i+1; j < 16; j++) {
|
|
uint dist = colorDistance(m_color[i], m_color[j]);
|
|
if( dist > best_dist ) {
|
|
best_dist = dist;
|
|
c0 = m_color[i];
|
|
c1 = m_color[j];
|
|
}
|
|
}
|
|
}
|
|
|
|
*start = c0;
|
|
*end = c1;
|
|
}
|
|
|
|
/// Get luminance color range.
|
|
void ColorBlock::luminanceRange(Color32 * start, Color32 * end) const
|
|
{
|
|
nvDebugCheck(start != NULL);
|
|
nvDebugCheck(end != NULL);
|
|
|
|
Color32 minColor, maxColor;
|
|
uint minLuminance, maxLuminance;
|
|
|
|
maxLuminance = minLuminance = colorLuminance(m_color[0]);
|
|
|
|
for(uint i = 1; i < 16; i++)
|
|
{
|
|
uint luminance = colorLuminance(m_color[i]);
|
|
|
|
if (luminance > maxLuminance) {
|
|
maxLuminance = luminance;
|
|
maxColor = m_color[i];
|
|
}
|
|
else if (luminance < minLuminance) {
|
|
minLuminance = luminance;
|
|
minColor = m_color[i];
|
|
}
|
|
}
|
|
|
|
*start = minColor;
|
|
*end = maxColor;
|
|
}
|
|
|
|
/// Get color range based on the bounding box.
|
|
void ColorBlock::boundsRange(Color32 * start, Color32 * end) const
|
|
{
|
|
nvDebugCheck(start != NULL);
|
|
nvDebugCheck(end != NULL);
|
|
|
|
Color32 minColor(255, 255, 255);
|
|
Color32 maxColor(0, 0, 0);
|
|
|
|
for(uint i = 0; i < 16; i++)
|
|
{
|
|
if (m_color[i].r < minColor.r) { minColor.r = m_color[i].r; }
|
|
if (m_color[i].g < minColor.g) { minColor.g = m_color[i].g; }
|
|
if (m_color[i].b < minColor.b) { minColor.b = m_color[i].b; }
|
|
if (m_color[i].r > maxColor.r) { maxColor.r = m_color[i].r; }
|
|
if (m_color[i].g > maxColor.g) { maxColor.g = m_color[i].g; }
|
|
if (m_color[i].b > maxColor.b) { maxColor.b = m_color[i].b; }
|
|
}
|
|
|
|
// Offset range by 1/16 of the extents
|
|
Color32 inset;
|
|
inset.r = (maxColor.r - minColor.r) >> 4;
|
|
inset.g = (maxColor.g - minColor.g) >> 4;
|
|
inset.b = (maxColor.b - minColor.b) >> 4;
|
|
|
|
minColor.r = (minColor.r + inset.r <= 255) ? minColor.r + inset.r : 255;
|
|
minColor.g = (minColor.g + inset.g <= 255) ? minColor.g + inset.g : 255;
|
|
minColor.b = (minColor.b + inset.b <= 255) ? minColor.b + inset.b : 255;
|
|
|
|
maxColor.r = (maxColor.r >= inset.r) ? maxColor.r - inset.r : 0;
|
|
maxColor.g = (maxColor.g >= inset.g) ? maxColor.g - inset.g : 0;
|
|
maxColor.b = (maxColor.b >= inset.b) ? maxColor.b - inset.b : 0;
|
|
|
|
*start = minColor;
|
|
*end = maxColor;
|
|
}
|
|
|
|
/// Get color range based on the bounding box.
|
|
void ColorBlock::boundsRangeAlpha(Color32 * start, Color32 * end) const
|
|
{
|
|
nvDebugCheck(start != NULL);
|
|
nvDebugCheck(end != NULL);
|
|
|
|
Color32 minColor(255, 255, 255, 255);
|
|
Color32 maxColor(0, 0, 0, 0);
|
|
|
|
for(uint i = 0; i < 16; i++)
|
|
{
|
|
if (m_color[i].r < minColor.r) { minColor.r = m_color[i].r; }
|
|
if (m_color[i].g < minColor.g) { minColor.g = m_color[i].g; }
|
|
if (m_color[i].b < minColor.b) { minColor.b = m_color[i].b; }
|
|
if (m_color[i].a < minColor.a) { minColor.a = m_color[i].a; }
|
|
if (m_color[i].r > maxColor.r) { maxColor.r = m_color[i].r; }
|
|
if (m_color[i].g > maxColor.g) { maxColor.g = m_color[i].g; }
|
|
if (m_color[i].b > maxColor.b) { maxColor.b = m_color[i].b; }
|
|
if (m_color[i].a > maxColor.a) { maxColor.a = m_color[i].a; }
|
|
}
|
|
|
|
// Offset range by 1/16 of the extents
|
|
Color32 inset;
|
|
inset.r = (maxColor.r - minColor.r) >> 4;
|
|
inset.g = (maxColor.g - minColor.g) >> 4;
|
|
inset.b = (maxColor.b - minColor.b) >> 4;
|
|
inset.a = (maxColor.a - minColor.a) >> 4;
|
|
|
|
minColor.r = (minColor.r + inset.r <= 255) ? minColor.r + inset.r : 255;
|
|
minColor.g = (minColor.g + inset.g <= 255) ? minColor.g + inset.g : 255;
|
|
minColor.b = (minColor.b + inset.b <= 255) ? minColor.b + inset.b : 255;
|
|
minColor.a = (minColor.a + inset.a <= 255) ? minColor.a + inset.a : 255;
|
|
|
|
maxColor.r = (maxColor.r >= inset.r) ? maxColor.r - inset.r : 0;
|
|
maxColor.g = (maxColor.g >= inset.g) ? maxColor.g - inset.g : 0;
|
|
maxColor.b = (maxColor.b >= inset.b) ? maxColor.b - inset.b : 0;
|
|
maxColor.a = (maxColor.a >= inset.a) ? maxColor.a - inset.a : 0;
|
|
|
|
*start = minColor;
|
|
*end = maxColor;
|
|
}
|
|
|
|
|
|
/// Sort colors by abosolute value in their 16 bit representation.
|
|
void ColorBlock::sortColorsByAbsoluteValue()
|
|
{
|
|
// Dummy selection sort.
|
|
for( uint a = 0; a < 16; a++ ) {
|
|
uint max = a;
|
|
Color16 cmax(m_color[a]);
|
|
|
|
for( uint b = a+1; b < 16; b++ ) {
|
|
Color16 cb(m_color[b]);
|
|
|
|
if( cb.u > cmax.u ) {
|
|
max = b;
|
|
cmax = cb;
|
|
}
|
|
}
|
|
swap( m_color[a], m_color[max] );
|
|
}
|
|
}
|
|
|
|
|
|
/// Find extreme colors in the given axis.
|
|
void ColorBlock::computeRange(Vector3::Arg axis, Color32 * start, Color32 * end) const
|
|
{
|
|
nvDebugCheck(start != NULL);
|
|
nvDebugCheck(end != NULL);
|
|
|
|
int mini, maxi;
|
|
mini = maxi = 0;
|
|
|
|
float min, max;
|
|
min = max = dot(Vector3(m_color[0].r, m_color[0].g, m_color[0].b), axis);
|
|
|
|
for(uint i = 1; i < 16; i++)
|
|
{
|
|
const Vector3 vec(m_color[i].r, m_color[i].g, m_color[i].b);
|
|
|
|
float val = dot(vec, axis);
|
|
if( val < min ) {
|
|
mini = i;
|
|
min = val;
|
|
}
|
|
else if( val > max ) {
|
|
maxi = i;
|
|
max = val;
|
|
}
|
|
}
|
|
|
|
*start = m_color[mini];
|
|
*end = m_color[maxi];
|
|
}
|
|
|
|
|
|
/// Sort colors in the given axis.
|
|
void ColorBlock::sortColors(const Vector3 & axis)
|
|
{
|
|
float luma_array[16];
|
|
|
|
for(uint i = 0; i < 16; i++) {
|
|
const Vector3 vec(m_color[i].r, m_color[i].g, m_color[i].b);
|
|
luma_array[i] = dot(vec, axis);
|
|
}
|
|
|
|
// Dummy selection sort.
|
|
for( uint a = 0; a < 16; a++ ) {
|
|
uint min = a;
|
|
for( uint b = a+1; b < 16; b++ ) {
|
|
if( luma_array[b] < luma_array[min] ) {
|
|
min = b;
|
|
}
|
|
}
|
|
swap( luma_array[a], luma_array[min] );
|
|
swap( m_color[a], m_color[min] );
|
|
}
|
|
}
|
|
|
|
|
|
/// Get the volume of the color block.
|
|
float ColorBlock::volume() const
|
|
{
|
|
Box bounds;
|
|
bounds.clearBounds();
|
|
|
|
for(int i = 0; i < 16; i++) {
|
|
const Vector3 point(m_color[i].r, m_color[i].g, m_color[i].b);
|
|
bounds.addPointToBounds(point);
|
|
}
|
|
|
|
return bounds.volume();
|
|
}
|
|
|
|
|