OpenGL

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Visual C++

3dGrid.cpp：源码内容
							/////////////////////////////////////////////////////////////////////////////
// 3dGrid.cpp : implementation file
//
// glOOP (OpenGL Object Oriented Programming library)
// Copyright (c) Craig Fahrnbach 1997, 1998
//
// OpenGL is a registered trademark of Silicon Graphics
//
//
// This program is provided for educational and personal use only and
// is provided without guarantee or warrantee expressed or implied.
//
// Commercial use is strickly prohibited without written permission
// from ImageWare Development.
//
// This program is -not- in the public domain.
//
/////////////////////////////////////////////////////////////////////////////
#include "stdafx.h"
#include "glOOP.h"
#include "math.h"
#ifdef _DEBUG
#define new DEBUG_NEW
#undef THIS_FILE
static char THIS_FILE[] = __FILE__;
#endif
/////////////////////////////////////////////////////////////////////////////
// C3dGrid
IMPLEMENT_DYNAMIC(C3dGrid, CObject)
/////////////////////////////////////////////////////////////////////////////
// C3dGrid construction
C3dGrid::C3dGrid()
{
	// Assign Default values to member attributes
	m_fGridWidth = 20.0f; 
	m_fGridDepth = 20.0f; 
	m_fSpacing	 = 1.0f;
	m_fLineWidth = 0.05f;
	m_fGridColor[0] = 0.50f; // light gray
	m_fGridColor[1] = 0.50f;
	m_fGridColor[2] = 0.50f;
	m_fGridColor[3] = 1.00f;
}
/////////////////////////////////////////////////////////////////////////////
// C3dGrid Destructor
C3dGrid::~C3dGrid()
{
}
C3dGrid* C3dGrid::Create(float fSpacing)
{
	C3dGrid* pGrid = new C3dGrid;
	ASSERT_VALID(pGrid);
	if(fSpacing)
		pGrid->m_fSpacing = (GLfloat)fSpacing;
	return pGrid;
}
void C3dGrid::SetSize(float fSpacing)
{
	m_fSpacing = (GLfloat)fSpacing;
}
void C3dGrid::PointToGrid(float *x, float *y, float *z)
{
   *x=Roundf(*x/m_fSpacing)*m_fSpacing;
   *y=Roundf(*y/m_fSpacing)*m_fSpacing;
   *z=Roundf(*z/m_fSpacing)*m_fSpacing;
}
void C3dGrid::Display(C3dWorld* pWorld, C3dCamera* pCamera)
{
	if(!pCamera)
		return;
	// Save our current state
	glPushAttrib(GL_ALL_ATTRIB_BITS);
	// Save our modelview matrix
	glPushMatrix();
	// Disable lighting calculations..
	glDisable(GL_LIGHTING);
	// Reset color parameters to default values
	glDisable(GL_TEXTURE_2D);
	glPolygonMode(GL_FRONT_AND_BACK, GL_LINE);
	glColor4fv(m_fGridColor);
	glLineWidth(m_fLineWidth);
	if(pCamera->m_iViewType == VIEW_ISO)
//		Grid3D(pCamera);
		GridXY(pCamera);
	else
	{
		if(pCamera->m_iViewType == VIEW_TOP)
		{
			GridXY(pCamera);
		}
		else if(pCamera->m_iViewType == VIEW_FRONT)
		{
			glRotatef(90.0f, 1.0f, 0.0f, 0.0f);
			GridXY(pCamera);
		}
		else if(pCamera->m_iViewType == VIEW_SIDE)
		{
			glRotatef(90.0f, 0.0f, 1.0f, 0.0f);
			glRotatef(90.0f, 0.0f, 0.0f, 1.0f);
			GridXY(pCamera);
		}
	}
	// Restore our modelview matrix
	glPopMatrix();
	// Restore our state
	glPopAttrib();
}
void C3dGrid::Grid3D(C3dCamera* pCamera)
{
	// Draw the bottom XY grid
	GridXY(pCamera);
	// Draw the back XZ grid
	glPushMatrix();		// Save our modelview matrix
	glTranslatef(0.0f, m_fGridDepth/2, m_fGridDepth/2);
	glRotatef(90.0f, 1.0f, 0.0f, 0.0f);
	GridXY(pCamera);
	glPopMatrix();		// Restore our modelview matrix
	// Draw the side YZ grid
	glPushMatrix();		// Save our modelview matrix
	glTranslatef(-m_fGridWidth/2, 0.0f, m_fGridWidth/2);
	glRotatef(90.0f, 0.0f, 1.0f, 0.0f);
	GridXY(pCamera);
	glPopMatrix();		// Restore our modelview matrix
}
void C3dGrid::GridXY(C3dCamera* pCamera)
{
	GLfloat x, y;
	// Draw the Vertical lines
	for(x=-(m_fGridWidth/2); x<=(m_fGridWidth/2); x+=m_fSpacing)
	{
		glBegin(GL_LINES);
			glVertex3f(x*m_fSpacing,  m_fGridDepth/2, 0.0f);	// top
			glVertex3f(x*m_fSpacing, -m_fGridDepth/2, 0.0f);	// bottom
		glEnd();
	}
	// Draw the Horizontal lines
	for(y=-(m_fGridDepth/2); y<=(m_fGridDepth/2); y+=m_fSpacing)
	{
		glBegin(GL_LINES);
			glVertex3f(-m_fGridWidth/2, y*m_fSpacing, 0.0f);	// left
			glVertex3f( m_fGridWidth/2, y*m_fSpacing, 0.0f);	// right
		glEnd();
	}
}

						