// license:BSD-3-Clause
// copyright-holders:Aaron Giles
/******************************************************************************
palette.c
Palette handling functions.
******************************************************************************/
#include <assert.h>
#include "palette.h"
#include <stdlib.h>
#include <math.h>
//**************************************************************************
// CONSTANTS
//**************************************************************************
const rgb_t rgb_t::black(0,0,0);
const rgb_t rgb_t::white(255,255,255);
// the colors below are commonly used screen colors
const rgb_t rgb_t::green(0, 255, 0);
const rgb_t rgb_t::amber(247, 170, 0);
//**************************************************************************
// INLINE FUNCTIONS
//**************************************************************************
//-------------------------------------------------
// adjust_palette_entry - adjust a palette
// entry for brightness
//-------------------------------------------------
inline rgb_t palette_t::adjust_palette_entry(rgb_t entry, float brightness, float contrast, const UINT8 *gamma_map)
{
int r = rgb_t::clamp(float(gamma_map[entry.r()]) * contrast + brightness);
int g = rgb_t::clamp(float(gamma_map[entry.g()]) * contrast + brightness);
int b = rgb_t::clamp(float(gamma_map[entry.b()]) * contrast + brightness);
int a = entry.a();
return rgb_t(a,r,g,b);
}
//**************************************************************************
// CLIENT DIRTY LIST MANAGEMENT
//**************************************************************************
//-------------------------------------------------
// dirty_state - constructor
//-------------------------------------------------
palette_client::dirty_state::dirty_state()
: m_mindirty(0),
m_maxdirty(0)
{
}
//-------------------------------------------------
// dirty_list - return the current list and
// min/max values
//-------------------------------------------------
const UINT32 *palette_client::dirty_state::dirty_list(UINT32 &mindirty, UINT32 &maxdirty)
{
// fill in the mindirty/maxdirty
mindirty = m_mindirty;
maxdirty = m_maxdirty;
// if nothing to report, report nothing
return (m_mindirty > m_maxdirty) ? nullptr : &m_dirty[0];
}
//-------------------------------------------------
// resize - resize the dirty array and mark all
// dirty
//-------------------------------------------------
void palette_client::dirty_state::resize(UINT32 colors)
{
// resize to the correct number of dwords and mark all entries dirty
UINT32 dirty_dwords = (colors + 31) / 32;
m_dirty.resize(dirty_dwords);
memset(&m_dirty[0], 0xff, dirty_dwords*4);
// mark all entries dirty
m_dirty[dirty_dwords - 1] &= (1 << (colors % 32)) - 1;
// set min/max
m_mindirty = 0;
m_maxdirty = colors - 1;
}
//-------------------------------------------------
// mark_dirty - mark a single entry dirty
//-------------------------------------------------
void palette_client::dirty_state::mark_dirty(UINT32 index)
{
m_dirty[index / 32] |= 1 << (index % 32);
m_mindirty = MIN(m_mindirty, index);
m_maxdirty = MAX(m_maxdirty, index);
}
//-------------------------------------------------
// reset - clear the dirty array to mark all
// entries as clean
//-------------------------------------------------
void palette_client::dirty_state::reset()
{
// erase relevant entries in the new live one
memset(&m_dirty[m_mindirty / 32], 0, ((m_maxdirty / 32) + 1 - (m_mindirty / 32)) * sizeof(UINT32));
m_mindirty = m_dirty.size() * 32 - 1;
m_maxdirty = 0;
}
//**************************************************************************
// PALETTE CLIENT
//**************************************************************************
//-------------------------------------------------
// palette_client - constructor
//-------------------------------------------------
palette_client::palette_client(palette_t &palette)
: m_palette(palette),
m_next(nullptr),
m_live(&m_dirty[0]),
m_previous(&m_dirty[1])
{
// add a reference to the palette
palette.ref();
// resize the dirty lists
UINT32 total_colors = palette.num_colors() * palette.num_groups();
m_dirty[0].resize(total_colors);
m_dirty[1].resize(total_colors);
// now add us to the list of clients
m_next = palette.m_client_list;
palette.m_client_list = this;
}
//-------------------------------------------------
// ~palette_client - destructor
//-------------------------------------------------
palette_client::~palette_client()
{
// first locate and remove ourself from our palette's list
for (palette_client **curptr = &m_palette.m_client_list; *curptr != nullptr; curptr = &(*curptr)->m_next)
if (*curptr == this)
{
*curptr = m_next;
break;
}
// now deref the palette
m_palette.deref();
}
//-------------------------------------------------
// dirty_list - atomically get the current dirty
// list for a client
//-------------------------------------------------
const UINT32 *palette_client::dirty_list(UINT32 &mindirty, UINT32 &maxdirty)
{
// if nothing to report, report nothing and don't swap
const UINT32 *result = m_live->dirty_list(mindirty, maxdirty);
if (result == nullptr)
return nullptr;
// swap the live and previous lists
dirty_state *temp = m_live;
m_live = m_previous;
m_previous = temp;
// reset new live one and return the pointer to the previous
m_live->reset();
return result;
}
//**************************************************************************
// PALETTE_T
//**************************************************************************
//-------------------------------------------------
// alloc - static allocator
//-------------------------------------------------
palette_t *palette_t::alloc(UINT32 numcolors, UINT32 numgroups)
{
return new palette_t(numcolors, numgroups);
}
//-------------------------------------------------
// palette_t - constructor
//-------------------------------------------------
palette_t::palette_t(UINT32 numcolors, UINT32 numgroups)
: m_refcount(1),
m_numcolors(numcolors),
m_numgroups(numgroups),
m_brightness(0.0f),
m_contrast(1.0f),
m_gamma(1.0f),
m_entry_color(numcolors),
m_entry_contrast(numcolors),
m_adjusted_color(numcolors * numgroups + 2),
m_adjusted_rgb15(numcolors * numgroups + 2),
m_group_bright(numgroups),
m_group_contrast(numgroups),
m_client_list(nullptr)
{
// initialize gamma map
for (UINT32 index = 0; index < 256; index++)
m_gamma_map[index] = index;
// initialize the per-entry data
for (UINT32 index = 0; index < numcolors; index++)
{
m_entry_color[index] = rgb_t::black;
m_entry_contrast[index] = 1.0f;
}
// initialize the per-group data
for (UINT32 index = 0; index < numgroups; index++)
{
m_group_bright[index] = 0.0f;
m_group_contrast[index] = 1.0f;
}
// initialize the expanded data
for (UINT32 index = 0; index < numcolors * numgroups; index++)
{
m_adjusted_color[index] = rgb_t::black;
m_adjusted_rgb15[index] = rgb_t::black.as_rgb15();
}
// add black and white as the last two colors
m_adjusted_color[numcolors * numgroups + 0] = rgb_t::black;
m_adjusted_rgb15[numcolors * numgroups + 0] = rgb_t::black.as_rgb15();
m_adjusted_color[numcolors * numgroups + 1] = rgb_t::white;
m_adjusted_rgb15[numcolors * numgroups + 1] = rgb_t::white.as_rgb15();
}
//-------------------------------------------------
// palette_t - destructor
//-------------------------------------------------
palette_t::~palette_t()
{
}
//-------------------------------------------------
// palette_t - destructor
//-------------------------------------------------
void palette_t::deref()
{
if (--m_refcount == 0)
delete this;
}
//-------------------------------------------------
// set_brightness - set the overall brightness
// for the palette
//-------------------------------------------------
void palette_t::set_brightness(float brightness)
{
// convert incoming value to normalized result
brightness = (brightness - 1.0f) * 256.0f;
// set the global brightness if changed
if (m_brightness == brightness)
return;
m_brightness = brightness;
// update across all indices in all groups
for (int groupnum = 0; groupnum < m_numgroups; groupnum++)
for (int index = 0; index < m_numcolors; index++)
update_adjusted_color(groupnum, index);
}
//-------------------------------------------------
// set_contrast - set the overall contrast for
// the palette
//-------------------------------------------------
void palette_t::set_contrast(float contrast)
{
// set the global contrast if changed
if (m_contrast == contrast)
return;
m_contrast = contrast;
// update across all indices in all groups
for (int groupnum = 0; groupnum < m_numgroups; groupnum++)
for (int index = 0; index < m_numcolors; index++)
update_adjusted_color(groupnum, index);
}
//-------------------------------------------------
// set_gamma - set the overall gamma for the
// palette
//-------------------------------------------------
void palette_t::set_gamma(float gamma)
{
// set the global gamma if changed
if (m_gamma == gamma)
return;
m_gamma = gamma;
// recompute the gamma map
gamma = 1.0f / gamma;
for (int index = 0; index < 256; index++)
{
float fval = float(index) * (1.0f / 255.0f);
float fresult = pow(fval, gamma);
m_gamma_map[index] = rgb_t::clamp(255.0f * fresult);
}
// update across all indices in all groups
for (int groupnum = 0; groupnum < m_numgroups; groupnum++)
for (int index = 0; index < m_numcolors; index++)
update_adjusted_color(groupnum, index);
}
//-------------------------------------------------
// entry_set_color - set the raw RGB color for a
// given palette index
//-------------------------------------------------
void palette_t::entry_set_color(UINT32 index, rgb_t rgb)
{
// if out of range, or unchanged, ignore
if (index >= m_numcolors || m_entry_color[index] == rgb)
return;
// set the color
m_entry_color[index] = rgb;
// update across all groups
for (int groupnum = 0; groupnum < m_numgroups; groupnum++)
update_adjusted_color(groupnum, index);
}
//-------------------------------------------------
// entry_set_red_level - set the red level for a
// given palette index
//-------------------------------------------------
void palette_t::entry_set_red_level(UINT32 index, UINT8 level)
{
// if out of range, or unchanged, ignore
if (index >= m_numcolors || m_entry_color[index].r() == level)
return;
// set the level
m_entry_color[index].set_r(level);
// update across all groups
for (int groupnum = 0; groupnum < m_numgroups; groupnum++)
update_adjusted_color(groupnum, index);
}
//-------------------------------------------------
// entry_set_green_level - set the green level for a
// given palette index
//-------------------------------------------------
void palette_t::entry_set_green_level(UINT32 index, UINT8 level)
{
// if out of range, or unchanged, ignore
if (index >= m_numcolors || m_entry_color[index].g() == level)
return;
// set the level
m_entry_color[index].set_g(level);
// update across all groups
for (int groupnum = 0; groupnum < m_numgroups; groupnum++)
update_adjusted_color(groupnum, index);
}
//-------------------------------------------------
// entry_set_blue_level - set the blue level for a
// given palette index
//-------------------------------------------------
void palette_t::entry_set_blue_level(UINT32 index, UINT8 level)
{
// if out of range, or unchanged, ignore
if (index >= m_numcolors || m_entry_color[index].b() == level)
return;
// set the level
m_entry_color[index].set_b(level);
// update across all groups
for (int groupnum = 0; groupnum < m_numgroups; groupnum++)
update_adjusted_color(groupnum, index);
}
//-------------------------------------------------
// entry_set_contrast - set the contrast
// adjustment for a single palette index
//-------------------------------------------------
void palette_t::entry_set_contrast(UINT32 index, float contrast)
{
// if out of range, or unchanged, ignore
if (index >= m_numcolors || m_entry_contrast[index] == contrast)
return;
// set the contrast
m_entry_contrast[index] = contrast;
// update across all groups
for (int groupnum = 0; groupnum < m_numgroups; groupnum++)
update_adjusted_color(groupnum, index);
}
//-------------------------------------------------
// group_set_brightness - configure overall
// brightness for a palette group
//-------------------------------------------------
void palette_t::group_set_brightness(UINT32 group, float brightness)
{
// convert incoming value to normalized result
brightness = (brightness - 1.0f) * 256.0f;
// if out of range, or unchanged, ignore
if (group >= m_numgroups || m_group_bright[group] == brightness)
return;
// set the contrast
m_group_bright[group] = brightness;
// update across all colors
for (int index = 0; index < m_numcolors; index++)
update_adjusted_color(group, index);
}
//-------------------------------------------------
// group_set_contrast - configure overall
// contrast for a palette group
//-------------------------------------------------
void palette_t::group_set_contrast(UINT32 group, float contrast)
{
// if out of range, or unchanged, ignore
if (group >= m_numgroups || m_group_contrast[group] == contrast)
return;
// set the contrast
m_group_contrast[group] = contrast;
// update across all colors
for (int index = 0; index < m_numcolors; index++)
update_adjusted_color(group, index);
}
//-------------------------------------------------
// normalize_range - normalize a range of palette
// entries
//-------------------------------------------------
void palette_t::normalize_range(UINT32 start, UINT32 end, int lum_min, int lum_max)
{
// clamp within range
start = MAX(start, 0);
end = MIN(end, m_numcolors - 1);
// find the minimum and maximum brightness of all the colors in the range
INT32 ymin = 1000 * 255, ymax = 0;
for (UINT32 index = start; index <= end; index++)
{
rgb_t rgb = m_entry_color[index];
UINT32 y = 299 * rgb.r() + 587 * rgb.g() + 114 * rgb.b();
ymin = MIN(ymin, y);
ymax = MAX(ymax, y);
}
// determine target minimum/maximum
INT32 tmin = (lum_min < 0) ? ((ymin + 500) / 1000) : lum_min;
INT32 tmax = (lum_max < 0) ? ((ymax + 500) / 1000) : lum_max;
// now normalize the palette
for (UINT32 index = start; index <= end; index++)
{
rgb_t rgb = m_entry_color[index];
INT32 y = 299 * rgb.r() + 587 * rgb.g() + 114 * rgb.b();
INT32 u = ((INT32)rgb.b()-y /1000)*492 / 1000;
INT32 v = ((INT32)rgb.r()-y / 1000)*877 / 1000;
INT32 target = tmin + ((y - ymin) * (tmax - tmin + 1)) / (ymax - ymin);
UINT8 r = rgb_t::clamp(target + 1140 * v / 1000);
UINT8 g = rgb_t::clamp(target - 395 * u / 1000 - 581 * v / 1000);
UINT8 b = rgb_t::clamp(target + 2032 * u / 1000);
entry_set_color(index, rgb_t(r, g, b));
}
}
/**
* @fn void palette_t::update_adjusted_color(UINT32 group, UINT32 index)
*
* @brief -------------------------------------------------
* update_adjusted_color - update a color index by group and index pair
* -------------------------------------------------.
*
* @param group The group.
* @param index Zero-based index of the.
*/
void palette_t::update_adjusted_color(UINT32 group, UINT32 index)
{
// compute the adjusted value
rgb_t adjusted = adjust_palette_entry(m_entry_color[index],
m_group_bright[group] + m_brightness,
m_group_contrast[group] * m_entry_contrast[index] * m_contrast,
m_gamma_map);
// if not different, ignore
UINT32 finalindex = group * m_numcolors + index;
if (m_adjusted_color[finalindex] == adjusted)
return;
// otherwise, modify the adjusted color array
m_adjusted_color[finalindex] = adjusted;
m_adjusted_rgb15[finalindex] = adjusted.as_rgb15();
// mark dirty in all clients
for (palette_client *client = m_client_list; client != nullptr; client = client->next())
client->mark_dirty(finalindex);
}