protot/3rdparty/bgfx/examples/common/cube_atlas.cpp

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2016-08-29 22:31:11 +02:00
/*
* Copyright 2013 Jeremie Roy. All rights reserved.
* License: https://github.com/bkaradzic/bgfx#license-bsd-2-clause
*/
#include "common.h"
#include <bgfx/bgfx.h>
#include <limits.h> // INT_MAX
#include <memory.h> // memset
#include <vector>
#include "cube_atlas.h"
class RectanglePacker
{
public:
RectanglePacker();
RectanglePacker(uint32_t _width, uint32_t _height);
/// non constructor initialization
void init(uint32_t _width, uint32_t _height);
/// find a suitable position for the given rectangle
/// @return true if the rectangle can be added, false otherwise
bool addRectangle(uint16_t _width, uint16_t _height, uint16_t& _outX, uint16_t& _outY);
/// return the used surface in squared unit
uint32_t getUsedSurface()
{
return m_usedSpace;
}
/// return the total available surface in squared unit
uint32_t getTotalSurface()
{
return m_width * m_height;
}
/// return the usage ratio of the available surface [0:1]
float getUsageRatio();
/// reset to initial state
void clear();
private:
int32_t fit(uint32_t _skylineNodeIndex, uint16_t _width, uint16_t _height);
/// Merges all skyline nodes that are at the same level.
void merge();
struct Node
{
Node(int16_t _x, int16_t _y, int16_t _width) : x(_x), y(_y), width(_width)
{
}
int16_t x; //< The starting x-coordinate (leftmost).
int16_t y; //< The y-coordinate of the skyline level line.
int32_t width; //< The line _width. The ending coordinate (inclusive) will be x+width-1.
};
uint32_t m_width; //< width (in pixels) of the underlying texture
uint32_t m_height; //< height (in pixels) of the underlying texture
uint32_t m_usedSpace; //< Surface used in squared pixel
std::vector<Node> m_skyline; //< node of the skyline algorithm
};
RectanglePacker::RectanglePacker()
: m_width(0)
, m_height(0)
, m_usedSpace(0)
{
}
RectanglePacker::RectanglePacker(uint32_t _width, uint32_t _height)
: m_width(_width)
, m_height(_height)
, m_usedSpace(0)
{
// We want a one pixel border around the whole atlas to avoid any artefact when
// sampling texture
m_skyline.push_back(Node(1, 1, uint16_t(_width - 2) ) );
}
void RectanglePacker::init(uint32_t _width, uint32_t _height)
{
BX_CHECK(_width > 2, "_width must be > 2");
BX_CHECK(_height > 2, "_height must be > 2");
m_width = _width;
m_height = _height;
m_usedSpace = 0;
m_skyline.clear();
// We want a one pixel border around the whole atlas to avoid any artifact when
// sampling texture
m_skyline.push_back(Node(1, 1, uint16_t(_width - 2) ) );
}
bool RectanglePacker::addRectangle(uint16_t _width, uint16_t _height, uint16_t& _outX, uint16_t& _outY)
{
int best_height, best_index;
int32_t best_width;
Node* node;
Node* prev;
_outX = 0;
_outY = 0;
best_height = INT_MAX;
best_index = -1;
best_width = INT_MAX;
for (uint16_t ii = 0, num = uint16_t(m_skyline.size() ); ii < num; ++ii)
{
int32_t yy = fit(ii, _width, _height);
if (yy >= 0)
{
node = &m_skyline[ii];
if ( ( (yy + _height) < best_height)
|| ( ( (yy + _height) == best_height) && (node->width < best_width) ) )
{
best_height = uint16_t(yy) + _height;
best_index = ii;
best_width = node->width;
_outX = node->x;
_outY = uint16_t(yy);
}
}
}
if (best_index == -1)
{
return false;
}
Node newNode(_outX, _outY + _height, _width);
m_skyline.insert(m_skyline.begin() + best_index, newNode);
for (uint16_t ii = uint16_t(best_index + 1), num = uint16_t(m_skyline.size() ); ii < num; ++ii)
{
node = &m_skyline[ii];
prev = &m_skyline[ii - 1];
if (node->x < (prev->x + prev->width) )
{
uint16_t shrink = uint16_t(prev->x + prev->width - node->x);
node->x += shrink;
node->width -= shrink;
if (node->width <= 0)
{
m_skyline.erase(m_skyline.begin() + ii);
--ii;
--num;
}
else
{
break;
}
}
else
{
break;
}
}
merge();
m_usedSpace += _width * _height;
return true;
}
float RectanglePacker::getUsageRatio()
{
uint32_t total = m_width * m_height;
if (total > 0)
{
return (float)m_usedSpace / (float)total;
}
return 0.0f;
}
void RectanglePacker::clear()
{
m_skyline.clear();
m_usedSpace = 0;
// We want a one pixel border around the whole atlas to avoid any artefact when
// sampling texture
m_skyline.push_back(Node(1, 1, uint16_t(m_width - 2) ) );
}
int32_t RectanglePacker::fit(uint32_t _skylineNodeIndex, uint16_t _width, uint16_t _height)
{
int32_t width = _width;
int32_t height = _height;
const Node& baseNode = m_skyline[_skylineNodeIndex];
int32_t xx = baseNode.x, yy;
int32_t widthLeft = width;
int32_t ii = _skylineNodeIndex;
if ( (xx + width) > (int32_t)(m_width - 1) )
{
return -1;
}
yy = baseNode.y;
while (widthLeft > 0)
{
const Node& node = m_skyline[ii];
if (node.y > yy)
{
yy = node.y;
}
if ( (yy + height) > (int32_t)(m_height - 1) )
{
return -1;
}
widthLeft -= node.width;
++ii;
}
return yy;
}
void RectanglePacker::merge()
{
Node* node;
Node* next;
uint32_t ii;
for (ii = 0; ii < m_skyline.size() - 1; ++ii)
{
node = (Node*) &m_skyline[ii];
next = (Node*) &m_skyline[ii + 1];
if (node->y == next->y)
{
node->width += next->width;
m_skyline.erase(m_skyline.begin() + ii + 1);
--ii;
}
}
}
struct Atlas::PackedLayer
{
RectanglePacker packer;
AtlasRegion faceRegion;
};
Atlas::Atlas(uint16_t _textureSize, uint16_t _maxRegionsCount)
: m_usedLayers(0)
, m_usedFaces(0)
, m_textureSize(_textureSize)
, m_regionCount(0)
, m_maxRegionCount(_maxRegionsCount)
{
BX_CHECK(_textureSize >= 64 && _textureSize <= 4096, "Invalid _textureSize %d.", _textureSize);
BX_CHECK(_maxRegionsCount >= 64 && _maxRegionsCount <= 32000, "Invalid _maxRegionsCount %d.", _maxRegionsCount);
init();
m_layers = new PackedLayer[24];
for (int ii = 0; ii < 24; ++ii)
{
m_layers[ii].packer.init(_textureSize, _textureSize);
}
m_regions = new AtlasRegion[_maxRegionsCount];
m_textureBuffer = new uint8_t[ _textureSize * _textureSize * 6 * 4 ];
memset(m_textureBuffer, 0, _textureSize * _textureSize * 6 * 4);
m_textureHandle = bgfx::createTextureCube(_textureSize
, false
, 1
, bgfx::TextureFormat::BGRA8
);
}
Atlas::Atlas(uint16_t _textureSize, const uint8_t* _textureBuffer, uint16_t _regionCount, const uint8_t* _regionBuffer, uint16_t _maxRegionsCount)
: m_usedLayers(24)
, m_usedFaces(6)
, m_textureSize(_textureSize)
, m_regionCount(_regionCount)
, m_maxRegionCount(_regionCount < _maxRegionsCount ? _regionCount : _maxRegionsCount)
{
BX_CHECK(_regionCount <= 64 && _maxRegionsCount <= 4096, "_regionCount %d, _maxRegionsCount %d", _regionCount, _maxRegionsCount);
init();
m_regions = new AtlasRegion[_regionCount];
m_textureBuffer = new uint8_t[getTextureBufferSize()];
memcpy(m_regions, _regionBuffer, _regionCount * sizeof(AtlasRegion) );
memcpy(m_textureBuffer, _textureBuffer, getTextureBufferSize() );
m_textureHandle = bgfx::createTextureCube(_textureSize
, false
, 1
, bgfx::TextureFormat::BGRA8
, BGFX_TEXTURE_NONE
, bgfx::makeRef(m_textureBuffer, getTextureBufferSize() )
);
}
Atlas::~Atlas()
{
bgfx::destroyTexture(m_textureHandle);
delete [] m_layers;
delete [] m_regions;
delete [] m_textureBuffer;
}
void Atlas::init()
{
m_texelSize = float(UINT16_MAX) / float(m_textureSize);
float texelHalf = m_texelSize/2.0f;
switch (bgfx::getRendererType() )
{
case bgfx::RendererType::Direct3D9:
m_texelOffset[0] = 0.0f;
m_texelOffset[1] = 0.0f;
break;
case bgfx::RendererType::Direct3D11:
case bgfx::RendererType::Direct3D12:
m_texelOffset[0] = texelHalf;
m_texelOffset[1] = texelHalf;
break;
default:
m_texelOffset[0] = texelHalf;
m_texelOffset[1] = -texelHalf;
break;
}
}
uint16_t Atlas::addRegion(uint16_t _width, uint16_t _height, const uint8_t* _bitmapBuffer, AtlasRegion::Type _type, uint16_t outline)
{
if (m_regionCount >= m_maxRegionCount)
{
return UINT16_MAX;
}
uint16_t xx = 0;
uint16_t yy = 0;
uint32_t idx = 0;
while (idx < m_usedLayers)
{
if (m_layers[idx].faceRegion.getType() == _type
&& m_layers[idx].packer.addRectangle(_width + 1, _height + 1, xx, yy) )
{
break;
}
idx++;
}
if (idx >= m_usedLayers)
{
if ( (idx + _type) > 24
|| m_usedFaces >= 6)
{
return UINT16_MAX;
}
for (int ii = 0; ii < _type; ++ii)
{
AtlasRegion& region = m_layers[idx + ii].faceRegion;
region.x = 0;
region.y = 0;
region.width = m_textureSize;
region.height = m_textureSize;
region.setMask(_type, m_usedFaces, ii);
}
m_usedLayers += _type;
m_usedFaces++;
if (!m_layers[idx].packer.addRectangle(_width + 1, _height + 1, xx, yy) )
{
return UINT16_MAX;
}
}
AtlasRegion& region = m_regions[m_regionCount];
region.x = xx;
region.y = yy;
region.width = _width;
region.height = _height;
region.mask = m_layers[idx].faceRegion.mask;
updateRegion(region, _bitmapBuffer);
region.x += outline;
region.y += outline;
region.width -= (outline * 2);
region.height -= (outline * 2);
return m_regionCount++;
}
void Atlas::updateRegion(const AtlasRegion& _region, const uint8_t* _bitmapBuffer)
{
uint32_t size = _region.width * _region.height * 4;
if (0 < size)
{
const bgfx::Memory* mem = bgfx::alloc(size);
memset(mem->data, 0, mem->size);
if (_region.getType() == AtlasRegion::TYPE_BGRA8)
{
const uint8_t* inLineBuffer = _bitmapBuffer;
uint8_t* outLineBuffer = m_textureBuffer + _region.getFaceIndex() * (m_textureSize * m_textureSize * 4) + ( ( (_region.y * m_textureSize) + _region.x) * 4);
for (int yy = 0; yy < _region.height; ++yy)
{
memcpy(outLineBuffer, inLineBuffer, _region.width * 4);
inLineBuffer += _region.width * 4;
outLineBuffer += m_textureSize * 4;
}
memcpy(mem->data, _bitmapBuffer, mem->size);
}
else
{
uint32_t layer = _region.getComponentIndex();
const uint8_t* inLineBuffer = _bitmapBuffer;
uint8_t* outLineBuffer = (m_textureBuffer + _region.getFaceIndex() * (m_textureSize * m_textureSize * 4) + ( ( (_region.y * m_textureSize) + _region.x) * 4) );
for (int yy = 0; yy < _region.height; ++yy)
{
for (int xx = 0; xx < _region.width; ++xx)
{
outLineBuffer[(xx * 4) + layer] = inLineBuffer[xx];
}
memcpy(mem->data + yy * _region.width * 4, outLineBuffer, _region.width * 4);
inLineBuffer += _region.width;
outLineBuffer += m_textureSize * 4;
}
}
bgfx::updateTextureCube(m_textureHandle, 0, (uint8_t)_region.getFaceIndex(), 0, _region.x, _region.y, _region.width, _region.height, mem);
}
}
void Atlas::packFaceLayerUV(uint32_t _idx, uint8_t* _vertexBuffer, uint32_t _offset, uint32_t _stride) const
{
packUV(m_layers[_idx].faceRegion, _vertexBuffer, _offset, _stride);
}
void Atlas::packUV(uint16_t _regionHandle, uint8_t* _vertexBuffer, uint32_t _offset, uint32_t _stride) const
{
const AtlasRegion& region = m_regions[_regionHandle];
packUV(region, _vertexBuffer, _offset, _stride);
}
static void writeUV(uint8_t* _vertexBuffer, int16_t _x, int16_t _y, int16_t _z, int16_t _w)
{
uint16_t* xyzw = (uint16_t*)_vertexBuffer;
xyzw[0] = _x;
xyzw[1] = _y;
xyzw[2] = _z;
xyzw[3] = _w;
}
void Atlas::packUV(const AtlasRegion& _region, uint8_t* _vertexBuffer, uint32_t _offset, uint32_t _stride) const
{
int16_t x0 = (int16_t)( ( (float)_region.x * m_texelSize + m_texelOffset[0]) - float(INT16_MAX) );
int16_t y0 = (int16_t)( ( (float)_region.y * m_texelSize + m_texelOffset[1]) - float(INT16_MAX) );
int16_t x1 = (int16_t)( ( ( (float)_region.x + _region.width) * m_texelSize + m_texelOffset[0]) - float(INT16_MAX) );
int16_t y1 = (int16_t)( ( ( (float)_region.y + _region.height) * m_texelSize + m_texelOffset[1]) - float(INT16_MAX) );
int16_t ww = (int16_t)( (float(INT16_MAX) / 4.0f) * (float)_region.getComponentIndex() );
_vertexBuffer += _offset;
switch (_region.getFaceIndex() )
{
case 0: // +X
x0 = -x0;
x1 = -x1;
y0 = -y0;
y1 = -y1;
writeUV(_vertexBuffer, INT16_MAX, y0, x0, ww); _vertexBuffer += _stride;
writeUV(_vertexBuffer, INT16_MAX, y1, x0, ww); _vertexBuffer += _stride;
writeUV(_vertexBuffer, INT16_MAX, y1, x1, ww); _vertexBuffer += _stride;
writeUV(_vertexBuffer, INT16_MAX, y0, x1, ww); _vertexBuffer += _stride;
break;
case 1: // -X
y0 = -y0;
y1 = -y1;
writeUV(_vertexBuffer, INT16_MIN, y0, x0, ww); _vertexBuffer += _stride;
writeUV(_vertexBuffer, INT16_MIN, y1, x0, ww); _vertexBuffer += _stride;
writeUV(_vertexBuffer, INT16_MIN, y1, x1, ww); _vertexBuffer += _stride;
writeUV(_vertexBuffer, INT16_MIN, y0, x1, ww); _vertexBuffer += _stride;
break;
case 2: // +Y
writeUV(_vertexBuffer, x0, INT16_MAX, y0, ww); _vertexBuffer += _stride;
writeUV(_vertexBuffer, x0, INT16_MAX, y1, ww); _vertexBuffer += _stride;
writeUV(_vertexBuffer, x1, INT16_MAX, y1, ww); _vertexBuffer += _stride;
writeUV(_vertexBuffer, x1, INT16_MAX, y0, ww); _vertexBuffer += _stride;
break;
case 3: // -Y
y0 = -y0;
y1 = -y1;
writeUV(_vertexBuffer, x0, INT16_MIN, y0, ww); _vertexBuffer += _stride;
writeUV(_vertexBuffer, x0, INT16_MIN, y1, ww); _vertexBuffer += _stride;
writeUV(_vertexBuffer, x1, INT16_MIN, y1, ww); _vertexBuffer += _stride;
writeUV(_vertexBuffer, x1, INT16_MIN, y0, ww); _vertexBuffer += _stride;
break;
case 4: // +Z
y0 = -y0;
y1 = -y1;
writeUV(_vertexBuffer, x0, y0, INT16_MAX, ww); _vertexBuffer += _stride;
writeUV(_vertexBuffer, x0, y1, INT16_MAX, ww); _vertexBuffer += _stride;
writeUV(_vertexBuffer, x1, y1, INT16_MAX, ww); _vertexBuffer += _stride;
writeUV(_vertexBuffer, x1, y0, INT16_MAX, ww); _vertexBuffer += _stride;
break;
case 5: // -Z
x0 = -x0;
x1 = -x1;
y0 = -y0;
y1 = -y1;
writeUV(_vertexBuffer, x0, y0, INT16_MIN, ww); _vertexBuffer += _stride;
writeUV(_vertexBuffer, x0, y1, INT16_MIN, ww); _vertexBuffer += _stride;
writeUV(_vertexBuffer, x1, y1, INT16_MIN, ww); _vertexBuffer += _stride;
writeUV(_vertexBuffer, x1, y0, INT16_MIN, ww); _vertexBuffer += _stride;
break;
}
}