[Scummvm-git-logs] scummvm master -> 5d3b85af6589fb46126314b52b6b4122a436a94f
bluegr
noreply at scummvm.org
Wed Jan 1 22:55:03 UTC 2025
This automated email contains information about 2 new commits which have been
pushed to the 'scummvm' repo located at https://github.com/scummvm/scummvm .
Summary:
19e707ce19 GRAPHICS: Add ColorQuantizer class
5d3b85af65 GRAPHICS: Remove obsolete FIXME comment
Commit: 19e707ce19028ae65a37edb08a8dd1867cd3afb5
https://github.com/scummvm/scummvm/commit/19e707ce19028ae65a37edb08a8dd1867cd3afb5
Author: Torbjörn Andersson (eriktorbjorn at users.sourceforge.net)
Date: 2025-01-02T00:54:58+02:00
Commit Message:
GRAPHICS: Add ColorQuantizer class
This simply moves the new ColorQuantizer class out of the SCUMM engine
and into the Graphics namespace where I think it belongs. It reduces a
potentially large number of colors into a reasonable palette of the
desired size.
The SCUMM engine uses this so that the Mac versions can present the
thumbnail image (which is at least 16 bpp) stored in savegames.
Changed paths:
A graphics/color_quantizer.cpp
A graphics/color_quantizer.h
engines/scumm/macgui/macgui_v6.cpp
engines/scumm/macgui/macgui_v6.h
graphics/module.mk
diff --git a/engines/scumm/macgui/macgui_v6.cpp b/engines/scumm/macgui/macgui_v6.cpp
index 32980e606bf..04ee75c7829 100644
--- a/engines/scumm/macgui/macgui_v6.cpp
+++ b/engines/scumm/macgui/macgui_v6.cpp
@@ -29,6 +29,7 @@
#include "engines/metaengine.h"
#include "engines/savestate.h"
+#include "graphics/color_quantizer.h"
#include "graphics/palette.h"
#include "graphics/paletteman.h"
#include "graphics/macgui/macwindowmanager.h"
@@ -554,7 +555,7 @@ void MacV6Gui::updateThumbnail(MacDialogWindow *window, Common::Rect drawArea, i
// use. Reduce the image to a smaller palette. We reserve 10 colors for
// the Mac GUI itself.
- ColorQuantizer quantizer(245);
+ Graphics::ColorQuantizer quantizer(245);
for (int y = yMin; y < yMax; y++) {
for (int x = 0; x < thumbnail->w; x++) {
diff --git a/engines/scumm/macgui/macgui_v6.h b/engines/scumm/macgui/macgui_v6.h
index a14a822440c..f255d9a3dfe 100644
--- a/engines/scumm/macgui/macgui_v6.h
+++ b/engines/scumm/macgui/macgui_v6.h
@@ -26,9 +26,6 @@
#include "common/rect.h"
#include "common/str.h"
-// For the color quantizer
-#include "common/stack.h"
-
namespace Scumm {
class MacGuiImpl;
@@ -91,250 +88,6 @@ protected:
bool runRestartDialog() override;
};
-// This code is heavily based on "Color Quantization using Octrees" by Dean
-// Clark, published in - I think - the January 1996 issue of Dr. Dobb's Journal.
-//
-// FIXME: The intention is that this should be moved to common code, but we keep
-// it here for now to avoid conflicts.
-
-#define kOctreeDepth 6
-
-struct OctreeNode {
- byte level;
- bool isLeaf;
- uint32 numPixels;
- uint32 sumRed;
- uint32 sumGreen;
- uint32 sumBlue;
- OctreeNode *child[8];
- OctreeNode *nextNode;
-};
-
-// An octree is a tree where each node has up to eight children. Colors are
-// inserted into it by looking at the bits of the R, G, and B components one
-// bit at a time, starting at the most significant bit. These three bits form
-// a value from 0 to 7, indicating which child node to enter.
-//
-// This means that adjacent leaves in the tree will represent colors that are
-// close together. Once the tree has more leaves than we want, we take all
-// leaves under one node, combine them, and make their parent a new leaf with
-// their average color. The old leaves are then discarded.
-//
-// The depth of the tree is the number of bits we look at. Technically this
-// would be eight, but six should be enough.
-
-class Octree {
-private:
- uint _leafLevel = kOctreeDepth - 1;
-
- OctreeNode *_root = nullptr;
- uint _numLeaves = 0;
- uint _maxLeaves = 0;
-
- OctreeNode *_reduceList[kOctreeDepth - 1];
- Common::Stack<OctreeNode *> _nodePool;
-
- OctreeNode *allocateNode(byte level) {
- OctreeNode *node;
-
- if (!_nodePool.empty())
- node = _nodePool.pop();
- else
- node = new OctreeNode();
-
- if (level == _leafLevel) {
- node->isLeaf = true;
- _numLeaves++;
- } else
- node->isLeaf = false;
-
- node->level = level;
- node->numPixels = 0;
- node->sumRed = 0;
- node->sumGreen = 0;
- node->sumBlue = 0;
- node->nextNode = nullptr;
-
- for (int i = 0; i < 8; i++)
- node->child[i] = nullptr;
-
- return node;
- }
-
- void releaseNode(OctreeNode *node) {
- _nodePool.push(node);
- }
-
- void deleteNodeRecursively(OctreeNode *node) {
- if (!node)
- return;
-
- for (int i = 0; i < 8; i++)
- deleteNodeRecursively(node->child[i]);
-
- delete node;
- }
-
- void insert(OctreeNode **node, byte r, byte g, byte b, uint level) {
- if (*node == nullptr) {
- *node = allocateNode(level);
- if (level != _leafLevel) {
- (*node)->nextNode = _reduceList[level];
- _reduceList[level] = *node;
- }
- }
-
- // Once we encounter a leaf, add the color there. This is not
- // necessarily at the bottom of the tree, so I guess it would
- // not be out of the question to transform the leaf into a
- // regular node. But I saw no mention of this in the article.
-
- if ((*node)->isLeaf) {
- (*node)->numPixels++;
- (*node)->sumRed += r;
- (*node)->sumGreen += g;
- (*node)->sumBlue += b;
- } else {
- byte bit = (0x80 >> level);
- byte rbit = (r & bit) >> (5 - level);
- byte gbit = (g & bit) >> (6 - level);
- byte bbit = (b & bit) >> (7 - level);
- int idx = rbit | gbit | bbit;
-
- insert(&((*node)->child[idx]), r, g, b, level + 1);
- }
-
- // Usually one reduction would be enough, but it's possible
- // that the reduction will not actually remove any leaves.
-
- while (_numLeaves > _maxLeaves)
- reduceTree();
- }
-
- void reduceTree() {
- // In the original article, once a reduce list has been emptied
- // the leaf level was decreased, meaning that the tree could
- // never again grow beyond that height. I don't understand why,
- // so I have made this a local variable instead.
-
- int level = _leafLevel - 1;
-
- while (!_reduceList[level])
- level--;
-
- // There are several possible approaches to picking the node to
- // reduce. Picking the one with the largest number of pixels
- // may leave more color for fine details. Picking the one with
- // the smallest number may sacrifice detail, but preserve subtle
- // gradations in large areas. This just picks the first one,
- // i.e. the most recently inserted one, so it's pretty random
- // which may be good on average.
- //
- // Once a subtree has been pruned, it will no longer grow back.
- // It seems to me it should be possible to allow it to, but the
- // article doesn't mention it. On the contrary, it states that
- // "any new colors whose path through the tree take them
- // through [a node that was turned into a leaf] now stop here".
-
- OctreeNode *node = _reduceList[level];
- _reduceList[level] = _reduceList[level]->nextNode;
-
- // Combine all the leaves into their parent, and make the
- // parent a leaf.
-
- uint32 sumRed = 0;
- uint32 sumGreen = 0;
- uint32 sumBlue = 0;
-
- byte numChildren = 0;
-
- for (int i = 0; i < 8; i++) {
- OctreeNode *child = node->child[i];
-
- if (child) {
- numChildren++;
- sumRed += child->sumRed;
- sumGreen += child->sumGreen;
- sumBlue += child->sumBlue;
- node->numPixels += child->numPixels;
- releaseNode(child);
- node->child[i] = nullptr;
- }
- }
-
- node->isLeaf = true;
- node->sumRed = sumRed;
- node->sumGreen = sumGreen;
- node->sumBlue = sumBlue;
-
- _numLeaves -= (numChildren - 1);
- }
-
- Graphics::Palette *_palette;
- uint _colorIndex;
-
- void getPalette(OctreeNode *node) {
- if (node->isLeaf) {
- byte r = node->sumRed / node->numPixels;
- byte g = node->sumGreen / node->numPixels;
- byte b = node->sumBlue / node->numPixels;
- _palette->set(_colorIndex, r, g, b);
- _colorIndex++;
- } else {
- for (uint i = 0; i < 8; i++) {
- if (node->child[i])
- getPalette(node->child[i]);
- }
- }
- }
-
-public:
- Octree(int maxLeaves) : _maxLeaves(maxLeaves) {
- for (uint i = 0; i < kOctreeDepth; i++)
- _reduceList[i] = nullptr;
- }
-
- ~Octree() {
- while (!_nodePool.empty())
- delete _nodePool.pop();
- deleteNodeRecursively(_root);
- }
-
- void insert(byte r, byte g, byte b) {
- insert(&_root, r, g, b, 0);
- }
-
- Graphics::Palette *getPalette() {
- _palette = new Graphics::Palette(_maxLeaves);
- _colorIndex = 0;
-
- getPalette(_root);
-
- return _palette;
- }
-};
-
-class ColorQuantizer {
-private:
- Octree *_octree = nullptr;
-
-public:
- ColorQuantizer(int maxColors) {
- _octree = new Octree(maxColors);
- }
-
- ~ColorQuantizer() {
- delete _octree;
- }
-
- void addColor(byte r, byte g, byte b) {
- _octree->insert(r, g, b);
- }
-
- Graphics::Palette *getPalette() {
- return _octree->getPalette();
- }
-};
-
} // End of namespace Scumm
+
#endif
diff --git a/graphics/color_quantizer.cpp b/graphics/color_quantizer.cpp
new file mode 100644
index 00000000000..21c351b0f5e
--- /dev/null
+++ b/graphics/color_quantizer.cpp
@@ -0,0 +1,268 @@
+/* ScummVM - Graphic Adventure Engine
+ *
+ * ScummVM is the legal property of its developers, whose names
+ * are too numerous to list here. Please refer to the COPYRIGHT
+ * file distributed with this source distribution.
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+
+#include "common/stack.h"
+
+#include "graphics/color_quantizer.h"
+#include "graphics/palette.h"
+
+namespace Graphics {
+
+// This code is heavily based on "Color Quantization using Octrees" by Dean
+// Clark, published in - I think - the January 1996 issue of Dr. Dobb's Journal.
+//
+// FIXME: The intention is that this should be moved to common code, but we keep
+// it here for now to avoid conflicts.
+
+#define kOctreeDepth 6
+
+struct OctreeNode {
+ byte level;
+ bool isLeaf;
+ uint32 numPixels;
+ uint32 sumRed;
+ uint32 sumGreen;
+ uint32 sumBlue;
+ OctreeNode *child[8];
+ OctreeNode *nextNode;
+};
+
+// An octree is a tree where each node has up to eight children. Colors are
+// inserted into it by looking at the bits of the R, G, and B components one
+// bit at a time, starting at the most significant bit. These three bits form
+// a value from 0 to 7, indicating which child node to enter.
+//
+// This means that adjacent leaves in the tree will represent colors that are
+// close together. Once the tree has more leaves than we want, we take all
+// leaves under one node, combine them, and make their parent a new leaf with
+// their average color. The old leaves are then discarded.
+//
+// The depth of the tree is the number of bits we look at. Technically this
+// would be eight, but six should be enough.
+
+class Octree {
+private:
+ uint _leafLevel = kOctreeDepth - 1;
+
+ OctreeNode *_root = nullptr;
+ uint _numLeaves = 0;
+ uint _maxLeaves = 0;
+
+ OctreeNode *_reduceList[kOctreeDepth - 1];
+ Common::Stack<OctreeNode *> _nodePool;
+
+ OctreeNode *allocateNode(byte level) {
+ OctreeNode *node;
+
+ if (!_nodePool.empty())
+ node = _nodePool.pop();
+ else
+ node = new OctreeNode();
+
+ if (level == _leafLevel) {
+ node->isLeaf = true;
+ _numLeaves++;
+ } else
+ node->isLeaf = false;
+
+ node->level = level;
+ node->numPixels = 0;
+ node->sumRed = 0;
+ node->sumGreen = 0;
+ node->sumBlue = 0;
+ node->nextNode = nullptr;
+
+ for (int i = 0; i < 8; i++)
+ node->child[i] = nullptr;
+
+ return node;
+ }
+
+ void releaseNode(OctreeNode *node) {
+ _nodePool.push(node);
+ }
+
+ void deleteNodeRecursively(OctreeNode *node) {
+ if (!node)
+ return;
+
+ for (int i = 0; i < 8; i++)
+ deleteNodeRecursively(node->child[i]);
+
+ delete node;
+ }
+
+ void insert(OctreeNode **node, byte r, byte g, byte b, uint level) {
+ if (*node == nullptr) {
+ *node = allocateNode(level);
+ if (level != _leafLevel) {
+ (*node)->nextNode = _reduceList[level];
+ _reduceList[level] = *node;
+ }
+ }
+
+ // Once we encounter a leaf, add the color there. This is not
+ // necessarily at the bottom of the tree, so I guess it would
+ // not be out of the question to transform the leaf into a
+ // regular node. But I saw no mention of this in the article.
+
+ if ((*node)->isLeaf) {
+ (*node)->numPixels++;
+ (*node)->sumRed += r;
+ (*node)->sumGreen += g;
+ (*node)->sumBlue += b;
+ } else {
+ byte bit = (0x80 >> level);
+ byte rbit = (r & bit) >> (5 - level);
+ byte gbit = (g & bit) >> (6 - level);
+ byte bbit = (b & bit) >> (7 - level);
+ int idx = rbit | gbit | bbit;
+
+ insert(&((*node)->child[idx]), r, g, b, level + 1);
+ }
+
+ // Usually one reduction would be enough, but it's possible
+ // that the reduction will not actually remove any leaves.
+
+ while (_numLeaves > _maxLeaves)
+ reduceTree();
+ }
+
+ void reduceTree() {
+ // In the original article, once a reduce list has been emptied
+ // the leaf level was decreased, meaning that the tree could
+ // never again grow beyond that height. I don't understand why,
+ // so I have made this a local variable instead.
+
+ int level = _leafLevel - 1;
+
+ while (!_reduceList[level])
+ level--;
+
+ // There are several possible approaches to picking the node to
+ // reduce. Picking the one with the largest number of pixels
+ // may leave more color for fine details. Picking the one with
+ // the smallest number may sacrifice detail, but preserve subtle
+ // gradations in large areas. This just picks the first one,
+ // i.e. the most recently inserted one, so it's pretty random
+ // which may be good on average.
+ //
+ // Once a subtree has been pruned, it will no longer grow back.
+ // It seems to me it should be possible to allow it to, but the
+ // article doesn't mention it. On the contrary, it states that
+ // "any new colors whose path through the tree take them
+ // through [a node that was turned into a leaf] now stop here".
+
+ OctreeNode *node = _reduceList[level];
+ _reduceList[level] = _reduceList[level]->nextNode;
+
+ // Combine all the leaves into their parent, and make the
+ // parent a leaf.
+
+ uint32 sumRed = 0;
+ uint32 sumGreen = 0;
+ uint32 sumBlue = 0;
+
+ byte numChildren = 0;
+
+ for (int i = 0; i < 8; i++) {
+ OctreeNode *child = node->child[i];
+
+ if (child) {
+ numChildren++;
+ sumRed += child->sumRed;
+ sumGreen += child->sumGreen;
+ sumBlue += child->sumBlue;
+ node->numPixels += child->numPixels;
+ releaseNode(child);
+ node->child[i] = nullptr;
+ }
+ }
+
+ node->isLeaf = true;
+ node->sumRed = sumRed;
+ node->sumGreen = sumGreen;
+ node->sumBlue = sumBlue;
+
+ _numLeaves -= (numChildren - 1);
+ }
+
+ Palette *_palette;
+ uint _colorIndex;
+
+ void getPalette(OctreeNode *node) {
+ if (node->isLeaf) {
+ byte r = node->sumRed / node->numPixels;
+ byte g = node->sumGreen / node->numPixels;
+ byte b = node->sumBlue / node->numPixels;
+ _palette->set(_colorIndex, r, g, b);
+ _colorIndex++;
+ } else {
+ for (uint i = 0; i < 8; i++) {
+ if (node->child[i])
+ getPalette(node->child[i]);
+ }
+ }
+ }
+
+public:
+ Octree(int maxLeaves) : _maxLeaves(maxLeaves) {
+ for (uint i = 0; i < kOctreeDepth; i++)
+ _reduceList[i] = nullptr;
+ }
+
+ ~Octree() {
+ while (!_nodePool.empty())
+ delete _nodePool.pop();
+ deleteNodeRecursively(_root);
+ }
+
+ void insert(byte r, byte g, byte b) {
+ insert(&_root, r, g, b, 0);
+ }
+
+ Palette *getPalette() {
+ _palette = new Graphics::Palette(_maxLeaves);
+ _colorIndex = 0;
+
+ getPalette(_root);
+
+ return _palette;
+ }
+};
+
+ColorQuantizer::ColorQuantizer(int maxColors) {
+ _octree = new Octree(maxColors);
+}
+
+ColorQuantizer::~ColorQuantizer() {
+ delete _octree;
+}
+
+void ColorQuantizer::addColor(byte r, byte g, byte b) {
+ _octree->insert(r, g, b);
+}
+
+Graphics::Palette *ColorQuantizer::getPalette() {
+ return _octree->getPalette();
+}
+
+} // End of namespace Graphics
diff --git a/graphics/color_quantizer.h b/graphics/color_quantizer.h
new file mode 100644
index 00000000000..1eab758bada
--- /dev/null
+++ b/graphics/color_quantizer.h
@@ -0,0 +1,70 @@
+/* ScummVM - Graphic Adventure Engine
+ *
+ * ScummVM is the legal property of its developers, whose names
+ * are too numerous to list here. Please refer to the COPYRIGHT
+ * file distributed with this source distribution.
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+
+#ifndef GRAPHICS_COLOR_QUANTIZER_H
+#define GRAPHICS_COLOR_QUANTIZER_H
+
+namespace Graphics {
+
+class Octree;
+class Palette;
+
+/**
+ * @brief Class for selecting a good palette from a large number of colors.
+ *
+ * Colors are added one by one, after which a palette with at most maxColors
+ * entries can be retrieved. The caller is responsible for freeing the palette
+ * afterwards.
+ */
+
+class ColorQuantizer {
+private:
+ Octree *_octree = nullptr;
+
+public:
+ /**
+ * @brief Construct a new ColorQuantizer object
+ *
+ * @param maxColors the maximum number of colors in the final palette
+ */
+ ColorQuantizer(int maxColors);
+ ~ColorQuantizer();
+
+ /**
+ * @brief Add a single color to the quantizer
+ *
+ * @param r the R component of the color
+ * @param g the G component of the color
+ * @param b the B component of the color
+ */
+ void addColor(byte r, byte g, byte b);
+
+ /**
+ * @brief Retrieve the resulting palette from the quantizer.
+ *
+ * @return A Palette object with at most maxColor entries.
+ */
+ Palette *getPalette();
+};
+
+} // End of namespace Graphics
+
+#endif
diff --git a/graphics/module.mk b/graphics/module.mk
index 9672721219e..55a3e9b6379 100644
--- a/graphics/module.mk
+++ b/graphics/module.mk
@@ -6,6 +6,7 @@ MODULE_OBJS := \
blit/blit-alpha.o \
blit/blit-generic.o \
blit/blit-scale.o \
+ color_quantizer.o \
cursorman.o \
font.o \
fontman.o \
Commit: 5d3b85af6589fb46126314b52b6b4122a436a94f
https://github.com/scummvm/scummvm/commit/5d3b85af6589fb46126314b52b6b4122a436a94f
Author: Torbjörn Andersson (eriktorbjorn at users.sourceforge.net)
Date: 2025-01-02T00:54:58+02:00
Commit Message:
GRAPHICS: Remove obsolete FIXME comment
Changed paths:
graphics/color_quantizer.cpp
diff --git a/graphics/color_quantizer.cpp b/graphics/color_quantizer.cpp
index 21c351b0f5e..c250e0d0b38 100644
--- a/graphics/color_quantizer.cpp
+++ b/graphics/color_quantizer.cpp
@@ -28,9 +28,6 @@ namespace Graphics {
// This code is heavily based on "Color Quantization using Octrees" by Dean
// Clark, published in - I think - the January 1996 issue of Dr. Dobb's Journal.
-//
-// FIXME: The intention is that this should be moved to common code, but we keep
-// it here for now to avoid conflicts.
#define kOctreeDepth 6
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