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Advanced Maya Texturing and Lighting- P7

Advanced Maya Texturing and Lighting- P7: I should stress that I am self-taught. In 1994, I sat down at a spare seat of Alias PowerAnimator 5.1 and started hacking away. After several years and various trials by fire, 3D became a livelihood, a love, and an obsession. Along the way, I was fortunate enough to work with many talented artists at Buena Vista Visual Effects and Pacific Data Images. In 2000, I switched from PowerAnimator to Maya and have since logged tens of thousands of hours with the subject of this book | appear. That is the upper edge of the texture is pinched into a single point as is the lower. For example in Figure 5.24 a Checker texture is mapped to a Surface Shader material as a Spherical projection. The top and bottom portion of the Checker is collapsed at the poles. A similar problem occurs with a NURBS sphere even though all NURBS surfaces have four edges two of the edges are collapsed into single points at the sphere s top and bottom pole. Figure 5.23 Planar projections mapped to various primitive surfaces. This scene is included on the CD as proj_plane.ma. 159 2D TEXTURE PROJECTION OPTIONS Note Although always visible a Projection utility s V Angle attribute is functional only for a Spherical projection type. U Angle is functional only for Spherical and Cylindrical projections. 160 Figure 5.24 Left A Spherical projection with default settings is applied to a sphere. Right The Spherical projection s U Angle is set to 360 and its V Angle is set to 180. This scene is included on the CD as proj_spherical.ma. CHAPTER 5 APPLYING 3D TEXTURES AND PROJECTIONS Ball Places the texture inside a projection sphere. The projection pinches the texture at only one pole. A real-world equivalent is a blanket draped over a ball with the blanket s four corners twisted together at one spot. The pole is indicated by the diamondshaped UV origin symbol on the projection icon see Figure 5.25 . Figure 5.25 Left A Ball projection is applied to a sphere. Middle The Ball projection icon. Right The test bitmap. This scene is included on the CD as proj_ball.ma. Cylindrical Places the texture inside a cylinder. The left and right edges of the texture will meet if the projection s U Angle is set to 360 degrees. The Cylindrical type creates two pinched poles at the top and bottom of the projection see Figure 5.26 . Figure 5.26 A Cylindrical projection applied to a sphere. This scene is included on the CD as proj_cylinder.ma. Cubic Places a texture onto the six faces of a cube see Figure .