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After adding your terrain effect, you should see a beautifully colored terrain on your screen. To improve this result, you ll extend your effect with normal mapping. At the end of this section, you ll have a normal-mapped, multitextured terrain. As with most effects, this will not change the shape of the terrain, as you will enhance only the visual quality of the image.winforms pdf 417 reader, winforms qr code reader, winforms upc-a reader, winforms data matrix reader, winforms ean 128 reader, winforms ean 13 reader, c# remove text from pdf, itextsharp replace text in pdf c#, winforms code 39 reader, c# remove text from pdf,
You will now look at the implementation of a mechanism to secure calls to the service layer based on the user who is currently logged in to the application. This is a classic crosscutting concern. I have chosen two methods from our service layer interface of Listing 5-1 to secure, and their signatures are shown in Listing 5-14.
Note Here, we briefly cover the changes required to enable your effect with normal mapping. The book
List<Timesheet> listTimesheets(UserAccount account); Timesheet findTimesheet(Long id); Between them, these two methods allow me to illustrate some of the most useful applications of AOP. Before the call to listTimesheets, we want to check whether the account details provided match those of the current user. We therefore need to intercept both the method and its return parameter. After the call to findTimesheet, we want to determine whether the timesheet returned belongs to the current user, so the aspect must be invoked after the method call and must have access to the return value of the method.
Real-Time Rendering, Second Edition, by Tomas Akenine-M ller and Eric Haines (AK Peters, Ltd., 2002) is a good reference for more information about the Phong algorithm and the normal mapping technique.
In the normal mapping technique, you adjust the normal in each pixel, as defined in a predefined normal map. The deviated normals stored in the normal map are specified in tangent space, which means you first need to find the x, y, and z axes of this tangent space. As explained earlier, these are defined by the normal, tangent, and binormal. Because these are different for each vertex, each vertex has a different tangent space, so this space should be calculated for each vertex in the vertex shader.
Note The specifics of how we acquire the authentication information for the currently logged-in user is
Add this code to your vertex shader to calculate the matrix that allows you to transform positions and vectors from world space to tangent space: float3x3 tangentSpace = float3x3(IN.tangent, IN.binormal, IN.normal); tangentSpace = mul(tangentSpace, matW); tangentSpace = transpose(tangentSpace); Remember that when you perform operations on two vectors, both vectors need to be defined in the same space. Because your normal is defined in tangent space, you ll want to transform all vectors needed for the lighting calculations into tangent space. Replace the corresponding part of your vertex shader with this code: // Light vectors float3 worldPosition = mul(IN.position, matW).xyz; OUT.eyeVec = mul(matVI.xyz - worldPosition, tangentSpace); OUT.lightVec1 = mul(light1Position - worldPosition, tangentSpace); OUT.lightVec2 = mul(light2Position - worldPosition, tangentSpace); Finally, you need to pass the texture coordinate for sampling in the normal map. This should be placed in the uv5 6 output, which still has two empty spaces: OUT.uv5 6 = float4(IN.uv0, IN.uv0 * uvNormalTile);
taken as a given in this chapter. The specifics are covered in 7, but the techniques described here apply regardless of how the user credentials are retrieved.
In your pixel shader, you need to find the adjusted normal vector. This is done by sampling the RGB color values from the normal map. Color values are constrained to the [0,1] interval; therefore, you need to scale them into the [-1,1] interval for the x, y, and z coordinates: float3 normal = tex2D(normalSampler, IN.uv5 6.zw); normal.xy = normal.xy * 2.0 - 1.0; Finally, the z component of the adjusted normal needs to be found so that the total length of the new normal is exactly 1.0: normal.z = sqrt(1.0 - dot(normal.xy, normal.xy));
The advice implementation class implements two methods, each parameterized for the value that will be intercepted: the user account parameter for the listTimesheets method and the return value of findTimesheet. Listing 5-15 shows these method signatures and the name of the class that implements them. (The full implementation of these methods is given in Listing 5-25, where the alternative use of annotations is explained.)
Figure 11-10 shows the final result of the terrain rendering. Notice that the terrain surface is flat. However, the normal map adds the detail of a stone pattern over the entire surface.