terrain3dtestview.cpp

模拟一架飞机在一个地形上空飞行的全过程

	if(nChar==49)	// 按下'1'键
	{
		_Throttle = 1;
	}
	if(nChar==50)	// 按下'2'键
	{
		_Throttle = 2;
	}
	if(nChar==51)	// 按下'3'键
	{
		_Throttle = 3;
	}
	if(nChar==52)	// 按下'4'键
	{
		_Throttle = 4;
	}	
	if(nChar==53)	// 按下'5'键
	{
		_Throttle = 5;
	}
	if(nChar==54)	// 按下'6'键
	{
		_Throttle = 6;
	}	
	if(nChar==55)	// 按下'7'键
	{
		_Throttle = 7;
	}
	if(nChar==56)	// 按下'8'键
	{
		_Throttle = 8;
	}
	if(nChar==57)	// 按下'9'键
	{
		_Throttle = 9;
	}
	if(nChar==48)	// 按下'0'键
	{
		_Throttle = 15;
	}

	if(nChar==VK_UP)
	{
		pitch -= 15 / (ABS(Speed)+1);
	}
	if(nChar==VK_DOWN)
	{
		pitch += 15 / (ABS(Speed)+1);
	}
	if(nChar==VK_LEFT)
	{
		zprot += 5/(ABS(Speed)+1);
		Throttle*=.99;               

	}
	if(nChar==VK_RIGHT)
	{
		zprot -= 5/(ABS(Speed)+1);
		Throttle*=.99;
	}

	if (Throttle == 15)
	{
		Afterburner = true;
	}
	else 
	{
		Afterburner = false;
	}

	if(nChar==76||nChar==108)		// 按下'L'键	
	{
		water=!water;
	}
	if(nChar==87||nChar==119)		// 按下'W'键
	{
		wireframe=!wireframe;  
	}	

	CView::OnKeyDown(nChar, nRepCnt, nFlags);
}

bool CTerrain3DTestView::InitTerrain(GLvoid)
{
	int i,i2;     
    
	field[0][0].y=(GLfloat(rand()%100)-50)/3;

	// 生成地形数据
	for (i = 0; i < MAX; i++)
	{  
		for (i2 = 0; i2 < MAX; i2++)
		{
			if (i<10 || i2<10 || i>MAX-10 || i2>MAX-10)
				field[i][i2].y=0;   
			else
				field[i][i2].y=(GLfloat(rand()%151)-75)/50+(field[i-1][i2-1].y+field[i-1][i2].y+field[i-1][i2+1].y+field[i-1][i2-2].y+field[i-1][i2+2].y)/5.05; //Calculate the y coordinate on the same principle. 				
		}
	}
	// 地形光滑处理
   for (int cnt = 0; cnt < 3; cnt++)
   {
	   for (int t = 1; t < MAX-1; t++)
	   {
		   for (int t2 = 1; t2 < MAX-1; t2++)
		   {
			   field[t][t2].y = (field[t+1][t2].y+field[t][t2-1].y+field[t-1][t2].y+field[t][t2+1].y)/4;           
			   if (cnt == 0)
			   {
				   if (field[t][t2].y < -1 && field[t][t2].y > -1-.5) 
					   field[t][t2].y -= .45, field[t][t2].y *= 2;
				   else if (field[t][t2].y > -1 && field[t][t2].y < -1+.5) 
					   field[t][t2].y += .5, field[t][t2].y /= 5;
			   }
		   }
	   }
   }
   return true;
}

bool CTerrain3DTestView::InitSmoke(GLvoid)
{
	// 粒子系统的初始化
	for (loop=0;loop<MAX_PARTICLES;loop++)				
	{
		particle[loop].active=true;					// 使所有的粒子激活
		particle[loop].life=1.0f;					// 给予新的生命
		particle[loop].fade=GLfloat(rand()%100)/7500 + 0.0075f;	// 随机淡化数值
		if (loop < MAX_PARTICLES/2) 
			particle[loop].x= .75f;
		else
			particle[loop].x= -.75f;
		particle[loop].y= -.15;						// Center On Y Axis
		particle[loop].z= 3;						// Center On Z Axis
		V = (GLfloat((rand()%5))+2)/5;
		Angle = GLfloat(rand()%360);
		particle[loop].zg = .15;
		particle[loop].xi = sin(Angle) * V;
		particle[loop].yi = cos(Angle) * V;
		particle[loop].zi = ((rand()%10)-5)/5;
	}
	return true;
}

bool CTerrain3DTestView::DrawWireframe(GLvoid)
{
	int i;    
	int i2;    
	int t, t2;
	glDisable(GL_TEXTURE_2D);
	glColor4f(0.0f,0.0f,0.0f,1.0f);
	for (t = xrange1; t < xrange2; t+=quality)
	{
		for (t2 = zrange1; t2 < zrange2; t2+=quality)
  		{
			i = t;
			i2 = t2;
            
			while (i < 0) i += MAX;             
			while (i > MAX) i -= MAX;            
			while (i2 < 0) i2 += MAX;             
			while (i2 > MAX) i2 -= MAX;
			int coord=t-MAX;
			int coord2=t2-MAX;

			glBegin(GL_LINE_LOOP);
			glVertex3f(coord,field[i][i2].y,coord2);        
			glVertex3f(coord+quality,field[i+quality][i2].y,coord2);
			glVertex3f(coord+quality,field[i+quality][i2+quality].y,coord2+quality);
			glVertex3f(coord,field[i][i2+quality].y,coord2+quality);
			glVertex3f(coord+quality,field[i+quality][i2].y,coord2);
			glEnd();
		}
	}
	glEnable(GL_TEXTURE_2D);
	  
	glLoadIdentity();
	glTranslatef(0,-.5f,-10);    
	glRotatef(yaw,0,1,0);
	glRotatef(zprot*15,0,0,1);
	glRotatef(pitch,1,0,0);

	glEnable(GL_LIGHTING);
	glCallList(MODEL);		// 绘制飞机模型
	glDisable(GL_LIGHTING);

	return true;
}

bool CTerrain3DTestView::DrawTexture(GLvoid)
{
	DrawTerrain();		// 绘制地形
	DrawSky();			// 绘制天空
	if(water)
	{ 
		DrawWater();	// 绘制水
	}         
   
	DrawPlane();		// 绘制飞机及其尾焰
	DrawSun();			// 绘制太阳
	return true;
}

bool CTerrain3DTestView::DrawWater(GLvoid)
{
	glEnable(GL_BLEND);
  	glLoadIdentity();
	glTranslatef(0,0,-10);
	glRotatef(sceneroty,0,1,0);
	glTranslatef(xtrans,ytrans-3.5-ABS(Speed)/5,ztrans);

	glBindTexture(GL_TEXTURE_2D, texture[6]);
	glColor4f(1,1,1,.35f);
	glBegin(GL_TRIANGLE_STRIP);
		glTexCoord2f(xtexa2,ytexa2); glVertex3f(xrange2-MAX,-1,zrange2-MAX);
		glTexCoord2f(xtexa2,ytexa);  glVertex3f(xrange2-MAX,-1,zrange1-MAX); 
		glTexCoord2f(xtexa,ytexa2);  glVertex3f(xrange1-MAX,-1,zrange2-MAX); 
		glTexCoord2f(xtexa,ytexa);   glVertex3f(xrange1-MAX,-1,zrange1-MAX); 
	glEnd();

	glDisable(GL_BLEND);
	return true;
}

bool CTerrain3DTestView::DrawSun(GLvoid)
{
	float sun_flare_size;
	sun_flare_size = 5000;
	glColor4f(1,.5f,0,.5f);
	glBegin(GL_TRIANGLE_STRIP);						// Build Quad From A Triangle Strip
		glTexCoord2f(1,1); glVertex3f(MAX/2+sun_flare_size,sun_height+sun_flare_size,sun_zdistance); // Top Right
		glTexCoord2f(0,1); glVertex3f(MAX/2-sun_flare_size,sun_height+sun_flare_size,sun_zdistance); // Top Left
		glTexCoord2f(1,0); glVertex3f(MAX/2+sun_flare_size,sun_height-sun_flare_size,sun_zdistance); // Bottom Right
		glTexCoord2f(0,0); glVertex3f(MAX/2-sun_flare_size,sun_height-sun_flare_size,sun_zdistance); // Bottom Left
	glEnd();										// Done Building Triangle Strip
	
	sun_flare_size = 500;
	glColor4f(1,.5f,0,1);
	glBegin(GL_TRIANGLE_STRIP);						// Build Quad From A Triangle Strip
		glTexCoord2f(1,1); glVertex3f(MAX/2+sun_flare_size,sun_height+sun_flare_size,sun_zdistance); // Top Right
		glTexCoord2f(0,1); glVertex3f(MAX/2-sun_flare_size,sun_height+sun_flare_size,sun_zdistance); // Top Left
		glTexCoord2f(1,0); glVertex3f(MAX/2+sun_flare_size,sun_height-sun_flare_size,sun_zdistance); // Bottom Right
		glTexCoord2f(0,0); glVertex3f(MAX/2-sun_flare_size,sun_height-sun_flare_size,sun_zdistance); // Bottom Left
	glEnd();										// Done Building Triangle Strip
	return true;

}

bool CTerrain3DTestView::DrawPlane(GLvoid)
{
	glColor4f(1,1,1,1);
	glLoadIdentity();
	glTranslatef(0,-.5f,-10);
     
	glRotatef(yaw,0,1,0);
	glRotatef(zprot*15,0,0,1);
	glRotatef(pitch,1,0,0);

	glEnable(GL_LIGHTING);
	glCallList(MODEL);		// 绘制飞机模型
	glDisable(GL_LIGHTING);

	glDisable(GL_DEPTH_TEST);
	glEnable(GL_ALPHA_TEST);
	glEnable(GL_BLEND);

	glBlendFunc(GL_SRC_ALPHA, GL_ONE);
	glBindTexture(GL_TEXTURE_2D,texture[5]);

	GLfloat exhaust_r, exhaust_g, exhaust_b;
	if (Afterburner)
	{
		exhaust_r = 1;
		exhaust_g = .5f;
		exhaust_b = 0;
	}
	else
	{
		exhaust_r = .5f;
		exhaust_g = .5f;
		exhaust_b = 1;
	}
	
	glowp += .5f-glow;    
	glow += glowp*(ABS(Throttle)/500);
	if (glow > 1) glow = 1;
	else if (glow < .25f) glow = .25f;
	glColor4f(exhaust_r,exhaust_g,exhaust_b,glow);
	float glowsize = 1;
	for (float glowpos = 3; glowpos <= 3.25f; glowpos+=.25f)
	{
		glowsize -= .175f;
		glBegin(GL_TRIANGLE_STRIP);						// Build Quad From A Triangle Strip
			glTexCoord2f(1,1); glVertex3f(.52+glowsize,-.8f+glowsize,glowpos); // Top Right
			glTexCoord2f(0,1); glVertex3f(.52-glowsize,-.8f+glowsize,glowpos); // Top Left
			glTexCoord2f(1,0); glVertex3f(.52+glowsize,-.8f-glowsize,glowpos); // Bottom Right
			glTexCoord2f(0,0); glVertex3f(.52-glowsize,-.8f-glowsize,glowpos); // Bottom Left
		glEnd();										// Done Building Triangle Strip
		glBegin(GL_TRIANGLE_STRIP);						// Build Quad From A Triangle Strip
			glTexCoord2f(1,1); glVertex3f(-.52+glowsize,-.8f+glowsize,glowpos); // Top Right
			glTexCoord2f(0,1); glVertex3f(-.52-glowsize,-.8f+glowsize,glowpos); // Top Left
			glTexCoord2f(1,0); glVertex3f(-.52+glowsize,-.8f-glowsize,glowpos); // Bottom Right
			glTexCoord2f(0,0); glVertex3f(-.52-glowsize,-.8f-glowsize,glowpos); // Bottom Left
		glEnd();										// Done Building Triangle Strip
	} 
	
	for (loop=0;loop<MAX_PARTICLES;loop++)					// Loop Through All The Particles
	{       	
		GLfloat x=particle[loop].x;						// Grab Our Particle X Position
		GLfloat y=particle[loop].y;						// Grab Our Particle Y Position
		GLfloat z=particle[loop].z;					// Particle Z Pos + Zoom           
		glColor4f(particle[loop].r,particle[loop].g,particle[loop].b,particle[loop].life/2);		  	                  
    
		glBegin(GL_TRIANGLE_STRIP);						// Build Quad From A Triangle Strip
			glTexCoord2f(1,1); glVertex3f(x+0.1f,y+0.1f,z); // Top Right
			glTexCoord2f(0,1); glVertex3f(x-0.1f,y+0.1f,z); // Top Left
			glTexCoord2f(1,0); glVertex3f(x+0.1f,y-0.1f,z); // Bottom Right
			glTexCoord2f(0,0); glVertex3f(x-0.1f,y-0.1f,z); // Bottom Left
		glEnd();										// Done Building Triangle Strip
            
		particle[loop].x+=particle[loop].xi/250;// Move On The X Axis By X Speed
		particle[loop].y+=particle[loop].yi/250;// Move On The Y Axis By Y Speed
		particle[loop].z+=particle[loop].zi/250;// Move On The Z Axis By Z Speed
		particle[loop].xi*=.975f;
		particle[loop].yi*=.975f;
		particle[loop].zi*=.975f;
		particle[loop].zi+=particle[loop].zg;			// Take Pull On Z Axis Into Account
		particle[loop].life-=particle[loop].fade*3;		// Reduce Particles Life By 'Fade'
		if (particle[loop].life < .5f) 
			particle[loop].life*=.975;

		if (particle[loop].life<0.05f)					// If Particle Is Burned Out
		{ 			    
			particle[loop].r=exhaust_r;
			particle[loop].g=exhaust_g;
			particle[loop].b=exhaust_b;
			
			particle[loop].life=1.0f;					// Give It New Life
			particle[loop].fade=GLfloat(rand()%100)/2500 + 0.02f;	// Random Fade Value
			if (loop < MAX_PARTICLES/2) 
				particle[loop].x= .52f;						
			else  
				particle[loop].x= -.52f;						
			particle[loop].y= -.8f;						
			particle[loop].z= 3.f;						
			V = (GLfloat((rand()%5))+2)/5;
			Angle = GLfloat(rand()%360);
              
			particle[loop].xi = sin(Angle) * V;
			particle[loop].yi = cos(Angle) * V;
			particle[loop].zi = ((rand()%10)-5)/5 + Throttle*4;
		}
	} 
	glDisable(GL_FOG);
	glLoadIdentity();
	glRotatef(sceneroty,0,1,0);
	return true;
}

bool CTerrain3DTestView::DrawTerrain(GLvoid)
{
	int i;    
	int i2;  
	int t, t2;	
	glEnable(GL_CULL_FACE);
	glFrontFace(GL_CCW);
	glColor4f(1,1,1,1);
	glBindTexture(GL_TEXTURE_2D, texture[0]);
	for (t = xrange1; t < xrange2; t+=quality)
	{        
		for (t2 = zrange1; t2 < zrange2; t2+=quality)
		{                                     
			i = t;
			i2 = t2;
            
			while (i < 0) i += MAX;             
			while (i > MAX) i -= MAX;            
			while (i2 < 0) i2 += MAX;             
			while (i2 > MAX) i2 -= MAX;

   			xtexa = (GLfloat(i)/MAX)*57;
			xtexa2 = (GLfloat(i+quality)/MAX)*57;    
			ytexa = (GLfloat(i2)/MAX)*57;
			ytexa2 = (GLfloat(i2+quality)/MAX)*57;       
			int coord=t-MAX;
			int coord2=t2-MAX;
      
			glBegin(GL_TRIANGLE_STRIP);
			glTexCoord2f(xtexa2,ytexa2);  glVertex3f(coord+quality,field[i+quality][i2+quality].y,  coord2+quality);
			glTexCoord2f(xtexa2,ytexa);   glVertex3f(coord+quality,field[i+quality][i2].y,coord2); 
			glTexCoord2f(xtexa,ytexa2);   glVertex3f(coord,field[i][i2+quality].y,coord2+quality); 
			glTexCoord2f(xtexa,ytexa);   glVertex3f(coord,field[i][i2].y,coord2); 
			glEnd();       
		}   
	}

	glEnable(GL_BLEND);
	glBlendFunc(GL_DST_COLOR, GL_ZERO);
	// 第二次绘制地形(多重纹理)
	glBindTexture(GL_TEXTURE_2D, texture[2]);
	glColor4f(1,1,1,.5f);
	for (t = xrange1; t < xrange2; t+=quality)
	{   
		for (t2 = zrange1; t2 < zrange2; t2+=quality)
		{               
			i = t;
			i2 = t2;
            
			while (i < 0) i += MAX;             
			while (i > MAX) i -= MAX;            
			while (i2 < 0) i2 += MAX;             
			while (i2 > MAX) i2 -= MAX;

			xtexa = (GLfloat(i)/MAX)*1;
			xtexa2 = (GLfloat(i+quality)/MAX)*1;
			ytexa = (GLfloat(i2)/MAX)*1;
			ytexa2 = (GLfloat(i2+quality)/MAX)*1;       
			int coord=t-MAX;
			int coord2=t2-MAX;
            
			glBegin(GL_TRIANGLE_STRIP);
			glTexCoord2f(xtexa2,ytexa2);  glVertex3f(coord+quality,field[i+quality][i2+quality].y,  coord2+quality);
			glTexCoord2f(xtexa2,ytexa);   glVertex3f(coord+quality,field[i+quality][i2].y,coord2); 
			glTexCoord2f(xtexa,ytexa2);   glVertex3f(coord,field[i][i2+quality].y,coord2+quality); 
			glTexCoord2f(xtexa,ytexa);   glVertex3f(coord,field[i][i2].y,coord2); 
			glEnd();            
		}
	}   
	glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
	glDisable(GL_BLEND);
       
	glFrontFace(GL_CW);
	glDisable(GL_CULL_FACE);
	return true;
}

bool CTerrain3DTestView::DrawSky(GLvoid)
{
	glFogf(GL_FOG_START, MAX*2);					// 雾的开始深度
	glFogf(GL_FOG_END, MAX*15);						// 雾的结束深度
	glColor4f(1,1,1,1);
	glBindTexture(GL_TEXTURE_2D, texture[1]);
	glTranslatef(-xtrans,-ytrans-MAX*48,-ztrans);
	glRotatef(90,1,0,1);
	gluSphere(quadratic,MAX*50,20,20);
	glFogf(GL_FOG_START, 10.0f);					// 雾的开始深度
	glFogf(GL_FOG_END, visual_distance);			// 雾的结束深度
	return true;
}

void CTerrain3DTestView::Caculate(GLvoid)
{
	zprot*=0.935f;
	heading += zprot/3;
	yaw += zprot/5;
	yaw*=.95f; 

	Throttlei += (_Throttle-Throttle)/10;
	Throttlei *= .9f;
	Throttle += Throttlei/10;
				
	GLfloat MAX_Speed = (sqrt(Throttle+1)) * 10; 
	Speedi += MAX_Speed-Speed;
	Speedi *= .9f;
	Speed += Speedi/1000;
	XP = -(GLfloat)sin(heading*piover180) * Speed;	
	YP = -(GLfloat)sin(pitch*piover180) * Speed;
	ZP = -(GLfloat)cos(heading*piover180) * Speed;
    GLfloat overallspeed = Hypot(Hypot(XP,YP),ZP) / (ABS(Speed)+1);  				
				
	YP *= overallspeed;
	XP *= overallspeed;
	ZP *= overallspeed;

	XPOS += XP/30;
	YPOS += YP/30;
	ZPOS += ZP/30;
}