Archief - [PROG]openGL renderen naar een FBO

glBindFramebufferEXT(GL_FRAMEBUFFER_EXT, g_fbo);
	glClearColor(0.0f, 1.0f, 0.0f, 1.0f);
	bindCgPrograms();
	glPushMatrix();
	glutSolidSphere(1.0,40,32);
	glPopMatrix();
	unBindCgPrograms();

	glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
	glLoadIdentity();

	// place camera/eye
	glTranslatef(xTranslate,yTranslate,zDepth);
	glRotatef(-yRotation,1.0,0.0,0.0);
	glRotatef(-xRotation,0.0,1.0,0.0);

	glReadBuffer(GL_COLOR_ATTACHMENT0_EXT);
    glReadPixels(0, 0, 500, 500,GL_RGBA,GL_FLOAT,result);
		printf("Data after roundtrip:\n");
		int i =0;
		while(i <= 500*500*4){
		std::cout << i << " : " << result[i] << result[i+1] << result[i+2] << result[i+3] << std::endl;
		i = i+4;
	}

void ashikhminShirleyVertexProgram(
	float4 position		: POSITION,
	float3 normal		: NORMAL,
	
	out float4 oPosition	: POSITION,
	out float3 objectPos	: TEXCOORD0,
	out float4 iPosition	: TEXCOORD1,
	out float3 oTangent		: TEXCOORD2,
	out float3 oNormal		: TEXCOORD3,
	out float3 oBinormal	: TEXCOORD4 )
{
	oPosition = mul(glstate.matrix.mvp, position);
	iPosition = position;
	float4 normal4;
	normal4.xyz = normal.xyz;
	normal4.w = 0;
	oNormal = mul(glstate.matrix.invtrans.modelview[0], normal4).xyz;
	
	float4 tangent;
	
	float3 c1 = cross(normal, float3(0.0, 0.0, 1.0));
	float3 c2 = cross(normal, float3(0.0, 1.0, 0.0));
	
	if(length(c1)>length(c2))
	{
		tangent.xyz = c1;	
	}
	else
	{
		tangent.xyz = c2;	
	}
	
	tangent.w = 0;
	oTangent = mul(glstate.matrix.invtrans.modelview[0], tangent).xyz;
	objectPos = position.xyz;
	

	oBinormal = cross(oTangent, oNormal);
}

void ashikhminShirleyFragmentProgram(
	float4 position		: TEXCOORD0,
	float4 iPosition	: TEXCOORD1,
	float3 tangent		: TEXCOORD2,
	float3 normal		: TEXCOORD3,
	float3 binormal		: TEXCOORD4,

	out float4 color	: COLOR,
	
	uniform float3 globalAmbient,
	uniform float3 lightColor,
	uniform float3 lightPosition,
	uniform float3 Ke,
	uniform float3 Ka,
	uniform float3 Kd,
	uniform float3 Ks,
	uniform float shininess )
{

	const float Pi = 3.14159;
	float Mx = 100;
	float My = 10;

	float3 P = mul(glstate.matrix.modelview[0], iPosition).xyz;
	float3 N = normalize(normal);
	float3 T = normalize(tangent);
	float3 B = normalize(binormal);
	
	float3 L = normalize(lightPosition - P);
	float3 V = normalize(-P);
	float3 H = normalize(L + V);
	
	
	// Compute the emissive term
	float3 emissive = Ke;

	// Compute the ambient term
	float3 ambient = Ka * globalAmbient;

	// Compute the diffuse term
	float3 diffuseFactor1 = ((28 * Kd) / (23 * Pi));
	float3 diffuseFactor2 = (1-Ks) * ( 1-pow(( 1- (dot(N, V)/2)),5));
	float3 diffuseFactor3 = ( 1- pow(( 1- (dot(N, L)/2)),5));
	
	float3 diffuse = diffuseFactor1 * diffuseFactor2 * diffuseFactor3;

	
	
	// Compute the specular term
	
	float specularFactor1 =  pow(((Mx+1)*(My+1)),0.5)/(8*Pi);
	float3 specularFactor2 = pow(dot(N, H),( ( (Mx*pow(dot(T, H),2)) + (My*pow(dot(B, H),2)))/(1-pow((dot(N, H)),2))));
	float3 specularFactor3 = dot(H, L) * max(dot(N, V), dot(N, L));
	float3 specularFresnel = Ks + (1-Ks)*pow((1-dot(H, L)),5);
	float3 specular = specularFactor1 * specularFactor2/specularFactor3 * specularFresnel;
	
	color.xyz = emissive + ambient + diffuse + specular;
	color.w = 1;
}

	normal4.xyz = normal.xyz;
	normal4.w = 0;