glGenFramebuffersEXT(1, &fb);// frame buffer
glGenTextures(1, &depth_tex);
glTexImage2D(GL_TEXTURE_2D, 0, GL_DEPTH_COMPONENT, 512, 512, 0,GL_DEPTH_COMPONENT, GL_FLOAT, NULL);

glBindFramebufferEXT(GL_FRAMEBUFFER_EXT, fb);
glFramebufferTexture2DEXT(GL_FRAMEBUFFER_EXT,
                          GL_DEPTH_ATTACHMENT_EXT,
                           GL_TEXTURE_2D, depth_tex, 0);

glDrawBuffer(GL_NONE);
glReadBuffer(GL_NONE);

draw scene here....

glBindFramebufferEXT(GL_FRAMEBUFFER_EXT, 0);

//preparing to pass this depth texture to shader

glUseProgramObjectARB(my_program);
int my_shadow=glGetUniformLocationARB(my_program,"shadowMap");

glActiveTexture(GL_TEXTURE2);
glBindTexture(GL_TEXTURE_2D, depth_tex);
glUniform1i(my_shadow,2);

glActiveTexture(GL_TEXTURE0);
glUseProgramObjectARB(0);

glDrawBuffer(GL_BACK);
glReadBuffer(GL_BACK);

//vertexuniform mat4 lightModel;uniform mat4 lightProj;uniform mat4 eyeModelInv;varying vec4 ShadowCoord ;void main(){		ShadowCoord	= lightProj * lightModel * eyeModelInv * gl_ModelViewMatrix  * gl_Vertex;											gl_Position	= ftransform();	gl_FrontColor = gl_Color;}//frag//uniform sampler2DShadow shadowMap;uniform sampler2D shadowMap;varying vec4 ShadowCoord ;void main(){	vec4 sdwCoor = ShadowCoord/ ShadowCoord.w;	sdwCoor = sdwCoor/2.0 + 0.5;		vec4 shadow = texture2D(shadowMap,sdwCoor.xy);	//vec4 shadow = shadow2DProj(shadowMap, sdwCoor);	float d = sdwCoor.z;		if(sdwCoor.x >1.0 || sdwCoor.x < 0.0 || sdwCoor.y>1.0 || sdwCoor.y<0.0)	gl_FragColor=gl_Color;	else	{			if(d >= shadow.x)			gl_FragColor=vec4(0.0,0.0,0.0,1.0);		else			gl_FragColor=gl_Color;					/*if(shadow.y!=1.0)			gl_FragColor=vec4(0.0,0.0,0.0,1.0);		else			gl_FragColor=gl_Color;*/	}			//gl_FragColor=shadow;	}