leocad/common/tr.cpp
2015-05-15 21:45:53 +00:00

267 lines
6.5 KiB
C++

// TR.cpp: implementation of the TiledRender class.
//
//////////////////////////////////////////////////////////////////////
#include "lc_global.h"
#include <math.h>
#include "tr.h"
//////////////////////////////////////////////////////////////////////
// Construction/Destruction
//////////////////////////////////////////////////////////////////////
TiledRender::TiledRender()
{
m_TileWidth = 256;
m_TileHeight = 256;
m_TileBorder = 0;
m_RowOrder = TR_BOTTOM_TO_TOP;
m_CurrentTile = -1;
m_ImageBuffer = 0;
m_TileBuffer = 0;
}
TiledRender::~TiledRender()
{
}
void TiledRender::TileSize(int width, int height, int border)
{
m_TileBorder = border;
m_TileWidth = width;
m_TileHeight = height;
m_TileWidthNB = width - 2 * border;
m_TileHeightNB = height - 2 * border;
}
void TiledRender::TileBuffer(TRenum format, TRenum type, void *image)
{
m_TileFormat = format;
m_TileType = type;
m_TileBuffer = image;
}
void TiledRender::ImageSize(int width, int height)
{
m_ImageWidth = width;
m_ImageHeight = height;
}
void TiledRender::ImageBuffer(TRenum format, TRenum type, void *image)
{
m_ImageFormat = format;
m_ImageType = type;
m_ImageBuffer = image;
}
void TiledRender::RowOrder(TRenum order)
{
if (order == TR_TOP_TO_BOTTOM || order == TR_BOTTOM_TO_TOP)
m_RowOrder = order;
}
int TiledRender::Get(TRenum param)
{
switch (param)
{
case TR_TILE_WIDTH:
return m_TileWidth;
case TR_TILE_HEIGHT:
return m_TileHeight;
case TR_TILE_BORDER:
return m_TileBorder;
case TR_IMAGE_WIDTH:
return m_ImageWidth;
case TR_IMAGE_HEIGHT:
return m_ImageHeight;
case TR_ROWS:
return m_Rows;
case TR_COLUMNS:
return m_Columns;
case TR_CURRENT_ROW:
if (m_CurrentTile < 0)
return -1;
else
return m_CurrentRow;
case TR_CURRENT_COLUMN:
if (m_CurrentTile < 0)
return -1;
else
return m_CurrentColumn;
case TR_CURRENT_TILE_WIDTH:
return m_CurrentTileWidth;
case TR_CURRENT_TILE_HEIGHT:
return m_CurrentTileHeight;
case TR_ROW_ORDER:
return (int) m_RowOrder;
default:
return 0;
}
}
void TiledRender::Ortho(double left, double right, double bottom, double top, double zNear, double zFar)
{
if (m_CurrentTile < 0)
{
m_Perspective = false;
m_Left = left;
m_Right = right;
m_Bottom = bottom;
m_Top = top;
m_Near = zNear;
m_Far = zFar;
}
}
void TiledRender::Frustum(double left, double right, double bottom, double top, double zNear, double zFar)
{
if (m_CurrentTile < 0)
{
m_Perspective = true;
m_Left = left;
m_Right = right;
m_Bottom = bottom;
m_Top = top;
m_Near = zNear;
m_Far = zFar;
}
}
void TiledRender::Perspective(double fovy, double aspect, double zNear, double zFar )
{
double xmin, xmax, ymin, ymax;
ymax = zNear * tan(fovy * 3.14159265 / 360.0);
ymin = -ymax;
xmin = ymin * aspect;
xmax = ymax * aspect;
Frustum(xmin, xmax, ymin, ymax, zNear, zFar);
}
void TiledRender::BeginTile()
{
GLint matrixMode;
int tileWidth, tileHeight, border;
double left, right, bottom, top;
if (m_CurrentTile <= 0)
{
m_Columns = (m_ImageWidth + m_TileWidthNB - 1) / m_TileWidthNB;
m_Rows = (m_ImageHeight + m_TileHeightNB - 1) / m_TileHeightNB;
m_CurrentTile = 0;
// Save user's viewport, will be restored after last tile rendered
glGetIntegerv(GL_VIEWPORT, m_ViewportSave);
}
// which tile (by row and column) we're about to render
if (m_RowOrder == TR_BOTTOM_TO_TOP)
{
m_CurrentRow = m_CurrentTile / m_Columns;
m_CurrentColumn = m_CurrentTile % m_Columns;
}
else if (m_RowOrder==TR_TOP_TO_BOTTOM)
{
m_CurrentRow = m_Rows - (m_CurrentTile / m_Columns) - 1;
m_CurrentColumn = m_CurrentTile % m_Columns;
}
border = m_TileBorder;
// Compute actual size of this tile with border
if (m_CurrentRow < m_Rows-1)
tileHeight = m_TileHeight;
else
tileHeight = m_ImageHeight - (m_Rows-1) * (m_TileHeightNB) + 2 * border;
if (m_CurrentColumn < m_Columns-1)
tileWidth = m_TileWidth;
else
tileWidth = m_ImageWidth - (m_Columns-1) * (m_TileWidthNB) + 2 * border;
// Save tile size, with border
m_CurrentTileWidth = tileWidth;
m_CurrentTileHeight = tileHeight;
glViewport(0, 0, tileWidth, tileHeight); // tile size including border
// save current matrix mode
glGetIntegerv(GL_MATRIX_MODE, &matrixMode);
glMatrixMode(GL_PROJECTION);
glLoadIdentity();
// compute projection parameters
left = m_Left + (m_Right - m_Left)
* (m_CurrentColumn * m_TileWidthNB - border) / m_ImageWidth;
right = left + (m_Right - m_Left) * tileWidth / m_ImageWidth;
bottom = m_Bottom + (m_Top - m_Bottom)
* (m_CurrentRow * m_TileHeightNB - border) / m_ImageHeight;
top = bottom + (m_Top - m_Bottom) * tileHeight / m_ImageHeight;
if (m_Perspective)
glFrustum(left, right, bottom, top, m_Near, m_Far);
else
glOrtho(left, right, bottom, top, m_Near, m_Far);
// restore user's matrix mode
glMatrixMode((GLenum)matrixMode);
}
int TiledRender::EndTile()
{
GLint prevRowLength, prevSkipRows, prevSkipPixels;
// be sure OpenGL rendering is finished
glFlush();
// save current glPixelStore values
glGetIntegerv(GL_PACK_ROW_LENGTH, &prevRowLength);
glGetIntegerv(GL_PACK_SKIP_ROWS, &prevSkipRows);
glGetIntegerv(GL_PACK_SKIP_PIXELS, &prevSkipPixels);
if (m_TileBuffer)
{
int srcX = m_TileBorder;
int srcY = m_TileBorder;
int srcWidth = m_TileWidthNB;
int srcHeight = m_TileHeightNB;
glReadPixels(srcX, srcY, srcWidth, srcHeight,
(GLenum)m_TileFormat, (GLenum)m_TileType, m_TileBuffer);
}
if (m_ImageBuffer)
{
int srcX = m_TileBorder;
int srcY = m_TileBorder;
int srcWidth = m_CurrentTileWidth - 2 * m_TileBorder;
int srcHeight = m_CurrentTileHeight - 2 * m_TileBorder;
int destX = m_TileWidthNB * m_CurrentColumn;
int destY = m_TileHeightNB * m_CurrentRow;
// setup pixel store for glReadPixels
glPixelStorei(GL_PACK_ROW_LENGTH, m_ImageWidth);
glPixelStorei(GL_PACK_SKIP_ROWS, destY);
glPixelStorei(GL_PACK_SKIP_PIXELS, destX);
// read the tile into the final image
glReadPixels(srcX, srcY, srcWidth, srcHeight,
(GLenum)m_ImageFormat, (GLenum)m_ImageType, m_ImageBuffer);
}
// restore previous glPixelStore values
glPixelStorei(GL_PACK_ROW_LENGTH, prevRowLength);
glPixelStorei(GL_PACK_SKIP_ROWS, prevSkipRows);
glPixelStorei(GL_PACK_SKIP_PIXELS, prevSkipPixels);
// increment tile counter, return 1 if more tiles left to render
m_CurrentTile++;
if (m_CurrentTile >= m_Rows * m_Columns)
{
// restore user's viewport
glViewport(m_ViewportSave[0], m_ViewportSave[1],
m_ViewportSave[2], m_ViewportSave[3]);
m_CurrentTile = -1; // all done
return 0;
}
else
return 1;
}