#!F-adobe-helvetica-medium-r-normal--18*
#!N 
#!N  #!Rtextmap Texture Mapping 
#!N #!N #!N If the machine on which Data Explorer is 
running supports OpenGL or GL, then texture mapping is available using 
hardware rendering. Texture mapping is the process of mapping an image 
(a field with 2-dimensional positions, quad connections, and colors) onto a 
geometry field with 2-dimensional connections and, typically, 3-dimensional positions (e.g., a 
color image mapped onto a rubbersheeted height field). The advantage of 
texture mapping over the use of Map, for example, is that 
the resulting image may have much greater resolution than the height 
map. #!N #!N The geometry field must have 2-D connections (triangles 
or quads) and must also have a component, with the name 
"uv," that is dependent on positions and provides the mapping between 
the image and the positions of the geometry field. This component 
consists of 2-vectors. The origin of the image will be mapped 
to the uv value [0 0], and the opposite corner to 
the uv value [1 1]. #!N #!N The texture map is 
the image to be mapped onto the geometry field. One requirement 
of the image (imposed by the hardware) is that the number 
of pixels in each dimension must be a power of 2 
greater than or equal to 32. The two dimensions do not 
have to be the same size. The texture map should be 
attached to the geometry field as an attribute, with the attribute 
name "texture," which can be done with the Options module. A 
texture-mapped image can be retrieved from the Display window using ReadImageWindow 
and then written to a file using WriteImage. #!N #!N #!T,1,216,356,641 
 #!F-adobe-times-bold-r-normal--18*   #!N TAB Attribute Name TAB Value TAB Description #!EF #!N 
TAB texture TAB a texture map TAB specifies a texture map 
#!N #!N Components #!N #!N The  #!F-adobe-times-bold-r-normal--18*   object #!EF input must 
have a "colors," "front colors," or "back colors" component. #!N #!N 
Script Language Examples #!N #!I0 #!N  #!F-adobe-times-medium-r-normal--18*   #!N #!N #!I30 #!N 
1. This example renders two views of the object and displays 
them in two separate windows, as specified by the  #!F-adobe-times-bold-r-normal--18*   where 
#!EF parameter. #!CForestGreen #!N #!N  #!F-adobe-courier-bold-r-normal--18*   #!N electrondensity = Import("/usr/local/dx/samples/data/watermolecule"); #!N 
isosurface = Isosurface(electrondensity, 0.3); #!N camera1 = AutoCamera(isosurface, "front", resolution=300); #!N 
camera2 = AutoCamera(isosurface, "top", resolution=300); #!N image1 = Render(isosurface, camera1); #!N 
image2 = Render(isosurface, camera2); #!N Display(image1,where="X, localhost:0, view from front"); #!N 
Display(image2,where="X, localhost:0, view from top"); #!EF #!N #!N #!EC #!N #!I30 
#!N 2. This example sets the rendering mode to "hardware" with 
the approximation method of "dots." #!CForestGreen #!N #!N  #!F-adobe-courier-bold-r-normal--18*   #!N electrondensity 
= Import("/usr/local/dx/samples/data/watermolecule"); #!N isosurface = Isosurface(electrondensity, 0.3); #!N from = Direction(65, 
5, 10); #!N camera = AutoCamera(isosurface, from); #!N isosurface=Options(isosurface, "rendering mode", 
"hardware", #!N "rendering approximation", "dots"); #!N Display(isosurface,camera); #!EF #!N #!N #!EC 
#!N #!I0 #!N #!EF #!N #!N #!N Example Visual Programs #!CForestGreen 
#!N #!N  #!F-adobe-courier-bold-r-normal--18*   #!N MovingCamera.net #!N PlotLine.net #!N PlotTwoLines.net #!N ReadImage.net 
#!N #!N ScaleScreen.net #!N #!N TextureMapOpenGL.net #!N UsingCompute.net #!N UsingMorph.net #!EF 
#!N #!N #!EC #!N #!N See Also #!N #!N  #!Larrange,dxall768 h Arrange  #!EL  , 
 #!Lcollect,dxall788 h Collect  #!EL  ,  #!Lfilter,dxall849 h Filter  #!EL  ,  #!Limage,dxall860 h Image  #!EL  ,  #!Lrender,dxall923 h Render  #!EL  ,  #!Lreduce,dxall918 h Reduce  #!EL  ,  #!Lrefine,dxall919 h Refine  #!EL  
,  #!Lscalscr,dxall935 h ScaleScreen  #!EL  ,  #!Lnormals,dxall897 h Normals  #!EL  ,  #!Lfacenor,dxall847 h FaceNormals  #!EL  ,  #!Lsupwind,dxall961 h SuperviseWindow  #!EL  ,  #!Lsupstat,dxall958 h SuperviseState  #!EL  , 
 #!Lreadimw,dxall916 h ReadImageWindow  #!EL  ,  #!Loptions,dxall898 h Options  #!EL  #!N #!N #!N  #!F-adobe-times-medium-i-normal--18*   Next Topic #!EF #!N 
#!N  #!Ldivcurl,dxall827 h DivCurl  #!EL  #!N  #!F-adobe-times-medium-i-normal--18*   #!N 
