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14<TITLE>OGRE Manual v1.2.0 ('Dagon'): Texture Units</TITLE>
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36<HR SIZE=1>
37<H3> 3.1.3 Texture Units </H3>
38<!--docid::SEC61::-->
39<P>
40
41Here are the attributes you can use in a 'texture_unit' section of a .material script:
42</P><P>
43
44<A NAME="SEC62"></A>
45<H2> Available Texture Layer Attributes </H2>
46<!--docid::SEC62::-->
47<UL>
48<LI>
49<A HREF="manual_17.html#SEC64">texture_alias</A>
50<LI>
51<A HREF="manual_17.html#SEC65">texture</A>
52<LI>
53<A HREF="manual_17.html#SEC66">anim_texture</A>
54<LI>
55<A HREF="manual_17.html#SEC67">cubic_texture</A>
56<LI>
57<A HREF="manual_17.html#SEC68">tex_coord_set</A>
58<LI>
59<A HREF="manual_17.html#SEC69">tex_address_mode</A>
60<LI>
61<A HREF="manual_17.html#SEC70">tex_border_colour</A>
62<LI>
63<A HREF="manual_17.html#SEC71">filtering</A>
64<LI>
65<A HREF="manual_17.html#SEC72">max_anisotropy</A>
66<LI>
67<A HREF="manual_17.html#SEC73">colour_op</A>
68<LI>
69<A HREF="manual_17.html#SEC74">colour_op_ex</A>
70<LI>
71<A HREF="manual_17.html#SEC75">colour_op_multipass_fallback</A>
72<LI>
73<A HREF="manual_17.html#SEC76">alpha_op_ex</A>
74<LI>
75<A HREF="manual_17.html#SEC77">env_map</A>
76<LI>
77<A HREF="manual_17.html#SEC78">scroll</A>
78<LI>
79<A HREF="manual_17.html#SEC79">scroll_anim</A>
80<LI>
81<A HREF="manual_17.html#SEC80">rotate</A>
82<LI>
83<A HREF="manual_17.html#SEC81">rotate_anim</A>
84<LI>
85<A HREF="manual_17.html#SEC82">scale</A>
86<LI>
87<A HREF="manual_17.html#SEC83">wave_xform</A>
88<LI>
89<A HREF="manual_17.html#SEC84">transform</A>
90</UL>
91<P>
92
93You can also use a nested 'texture_source' section in order to use a special add-in as a source of texture data, See section <A HREF="manual_61.html#SEC263">6. External Texture Sources</A> for details.
94</P><P>
95
96<A NAME="SEC63"></A>
97<H2> Attribute Descriptions  </H2>
98<!--docid::SEC63::-->
99<A NAME="texture_alias"></A>
100<A NAME="SEC64"></A>
101<H3> texture_alias </H3>
102<!--docid::SEC64::-->
103<P>
104
105Sets the alias name for this texture unit.<BR><BR>
106</P><P>
107
108Format: texture_alias &#60;name&#62;<BR><BR>
109</P><P>
110
111Example: texture_alias NormalMap<BR><BR>
112</P><P>
113
114Setting the texture alias name is usefull if this material is to be copied by other other materials and only the textures will be changed in the new material.(See section <A HREF="manual_20.html#SEC106">3.1.6 Copying Materials</A>)<BR><BR>
115Default: If a texture_unit has a name then the texture_alias defaults to the texture_unit name.
116</P><P>
117
118<A NAME="texture"></A>
119<A NAME="SEC65"></A>
120<H3> texture </H3>
121<!--docid::SEC65::-->
122<P>
123
124Sets the name of the static texture image this layer will use.<BR><BR>
125</P><P>
126
127Format: texture &#60;texturename&#62; [&#60;type&#62;] [numMipMaps] [alpha]<BR><BR>
128</P><P>
129
130Example: texture funkywall.jpg<BR><BR>
131</P><P>
132
133This setting is mutually exclusive with the anim_texture attribute. Note that the texture file cannot include spaces. Those of you Windows users who like spaces in filenames, please get over it and use underscores instead.<BR><BR>
134The 'type' parameter allows you to specify a the type of texture to create - the default is '2d', but you can override this; here's the full list:
135<DL COMPACT>
136<DT>1d
137<DD>A 1-dimensional texture; that is, a texture which is only 1 pixel high. These kinds of textures can be useful when you need to encode a function in a texture and use it as a simple lookup, perhaps in a fragment program. It is important that you use this setting when you use a fragment program which uses 1-dimensional texture coordinates, since GL requires you to use a texture type that matches (D3D will let you get away with it, but you ought to plan for cross-compatibility). Your texture widths should still be a power of 2 for best compatibility and performance.
138<DT>2d
139<DD>The default type which is assumed if you omit it, your texture has a width and a height, both of which should preferably be powers of 2, and if you can, make them square because this will look best on the most hardware. These can be addressed with 2D texture coordinates.
140<DT>3d
141<DD>A 3 dimensional texture ie volume texture. Your texture has a width, a height, both of which should be powers of 2, and has depth. These can be addressed with 3d texture coordinates ie through a pixel shader.
142<DT>cubic
143<DD>This texture is made up of 6 2D textures which are pasted around the inside of a cube. Can be addressed with 3D texture coordinates and are useful for cubic reflection maps and normal maps.
144</DL>
145The 'numMipMaps' option allows you to specify the number of mipmaps to generate for this texture. The default is 'unlimited' which means mips down to 1x1 size are generated. You can specify a fixed number (even 0) if you like instead. Note that if you use the same texture in many material scripts, the number of mipmaps generated will conform to the number specified in the first texture_unit used to load the texture - so be consistent with your usage.<BR><BR>
146<P>
147
148Finally, the 'alpha' option allows you to specify that a single channel (luminence) texture should be loaded as alpha, rather than the default which is to load it into the red channel. This can be helpful if you want to use alpha-only textures in the fixed function pipeline.
149</P><P>
150
151Default: none<BR><BR>
152</P><P>
153
154<A NAME="anim_texture"></A>
155<A NAME="SEC66"></A>
156<H3> anim_texture </H3>
157<!--docid::SEC66::-->
158<P>
159
160Sets the images to be used in an animated texture layer. In this case an animated texture layer means one which has multiple frames, each of which is a separate image file. There are 2 formats, one for implicitly determined image names, one for explicitly named images.<BR><BR>
161</P><P>
162
163Format1 (short): anim_texture &#60;base_name&#62; &#60;num_frames&#62; &#60;duration&#62;<BR><BR>
164</P><P>
165
166Example: anim_texture flame.jpg 5 2.5<BR><BR>
167</P><P>
168
169This sets up an animated texture layer made up of 5 frames named flame_0.jpg, flame_1.jpg, flame_2.jpg etc, with an animation length of 2.5 seconds (2fps). If duration is set to 0, then no automatic transition takes place and frames must be changed manually in code.<BR><BR>
170</P><P>
171
172Format2 (long): anim_texture &#60;frame1&#62; &#60;frame2&#62; ... &#60;duration&#62;<BR><BR>
173</P><P>
174
175Example: anim_texture flamestart.jpg flamemore.png flameagain.jpg moreflame.jpg lastflame.tga 2.5<BR><BR>
176</P><P>
177
178This sets up the same duration animation but from 5 separately named image files. The first format is more concise, but the second is provided if you cannot make your images conform to the naming standard required for it. <BR><BR>
179</P><P>
180
181Default: none<BR><BR>
182</P><P>
183
184<A NAME="cubic_texture"></A>
185<A NAME="SEC67"></A>
186<H3> cubic_texture </H3>
187<!--docid::SEC67::-->
188<P>
189
190Sets the images used in a cubic texture, i.e. one made up of 6 individual images making up the faces of a cube. These kinds of textures are used for reflection maps (if hardware supports cubic reflection maps) or skyboxes. There are 2 formats, a brief format expecting image names of a particular format and a more flexible but longer format for arbitrarily named textures.<BR><BR>
191</P><P>
192
193Format1 (short): cubic_texture &#60;base_name&#62; &#60;combinedUVW|separateUV&#62;<BR><BR>
194</P><P>
195
196The base_name in this format is something like 'skybox.jpg', and the system will expect you to provide skybox_fr.jpg, skybox_bk.jpg, skybox_up.jpg, skybox_dn.jpg, skybox_lf.jpg, and skybox_rt.jpg for the individual faces.<BR><BR>
197</P><P>
198
199Format2 (long): cubic_texture &#60;front&#62; &#60;back&#62; &#60;left&#62; &#60;right&#62; &#60;up&#62; &#60;down&#62; separateUV<BR><BR>
200</P><P>
201
202In this case each face is specified explicitly, incase you don't want to conform to the image naming standards above. You can only use this for the separateUV version since the combinedUVW version requires a single texture name to be assigned to the combined 3D texture (see below).<BR><BR>
203</P><P>
204
205In both cases the final parameter means the following:
206<DL COMPACT>
207<DT>combinedUVW
208<DD>    The 6 textures are combined into a single 'cubic' texture map which is then addressed using 3D texture coordinates with U, V and W components. Necessary for reflection maps since you never know which face of the box you are going to need. Note that not all cards support cubic environment mapping.
209<DT>separateUV
210<DD>    The 6 textures are kept separate but are all referenced by this single texture layer. One texture at a time is active (they are actually stored as 6 frames), and they are addressed using standard 2D UV coordinates. This type is good for skyboxes since only one face is rendered at one time and this has more guaranteed hardware support on older cards.
211</DL>
212<BR>
213Default: none
214<P>
215
216<A NAME="tex_coord_set"></A>
217<A NAME="SEC68"></A>
218<H3> tex_coord_set </H3>
219<!--docid::SEC68::-->
220<P>
221
222Sets which texture coordinate set is to be used for this texture layer. A mesh can define multiple sets of texture coordinates, this sets which one this material uses.<BR><BR>
223</P><P>
224
225Format: tex_coord_set &#60;set_num&#62;<BR><BR>
226</P><P>
227
228Example: tex_coord_set 2<BR><BR>
229</P><P>
230
231Default: tex_coord_set 0<BR><BR>
232</P><P>
233
234<A NAME="tex_address_mode"></A>
235<A NAME="SEC69"></A>
236<H3> tex_address_mode </H3>
237<!--docid::SEC69::-->
238Defines what happens when texture coordinates exceed 1.0 for this texture layer.You can use the simple format to specify the addressing mode for all 3 potential texture coordinates at once, or you can use the 2/3 parameter extended format to specify a different mode per texture coordinate. <BR><BR>
239<P>
240
241Simple Format: tex_address_mode &#60;uvw_mode&#62; <BR>
242Extended Format: tex_address_mode &#60;u_mode&#62; &#60;v_mode&#62; [&#60;w_mode&#62;]
243<DL COMPACT>
244<DT>wrap
245<DD>    Any value beyond 1.0 wraps back to 0.0. Texture is repeated.
246<DT>clamp
247<DD>    Values beyond 1.0 are clamped to 1.0. Texture 'streaks' beyond 1.0 since last line of pixels is used across the rest of the address space. Useful for textures which need exact coverage from 0.0 to 1.0 without the 'fuzzy edge' wrap gives when combined with filtering.
248<DT>mirror
249<DD>    Texture flips every boundary, meaning texture is mirrored every 1.0 u or v
250<DT>border
251<DD>    Values outside the range [0.0, 1.0] are set to the border colour, you might also set the <A HREF="manual_17.html#SEC70">tex_border_colour</A> attribute too.
252</DL>
253<BR>
254Default: tex_address_mode wrap<BR><BR>
255<P>
256
257<A NAME="tex_border_colour"></A>
258<A NAME="SEC70"></A>
259<H3> tex_border_colour </H3>
260<!--docid::SEC70::-->
261<P>
262
263Sets the border colour of border texture address mode (see <A HREF="manual_17.html#SEC69">tex_address_mode</A>). <BR><BR>
264</P><P>
265
266Format: tex_border_colour &#60;red&#62; &#60;green&#62; &#60;blue&#62; [&#60;alpha&#62;]<BR>
267NB valid colour values are between 0.0 and 1.0.<BR><BR>
268</P><P>
269
270Example: tex_border_colour 0.0 1.0 0.3<BR><BR>
271</P><P>
272
273Default: tex_border_colour 0.0 0.0 0.0 1.0<BR><BR>
274</P><P>
275
276<A NAME="filtering"></A>
277<A NAME="SEC71"></A>
278<H3> filtering </H3>
279<!--docid::SEC71::-->
280<P>
281
282Sets the type of texture filtering used when magnifying or minifying a texture. There are 2 formats to this attribute, the simple format where you simply specify the name of a predefined set of filtering options, and the complex format, where you individually set the minification, magnification, and mip filters yourself.<BR><BR>
283<STRONG>Simple Format</STRONG><BR>
284Format: filtering &#60;none|bilinear|trilinear|anisotropic&#62;<BR>
285Default: filtering bilinear<BR><BR>
286With this format, you only need to provide a single parameter which is one of the following:
287<DL COMPACT>
288<DT>none
289<DD>    No filtering or mipmapping is used. This is equivalent to the complex format 'filtering point point none'.
290<DT>bilinear
291<DD>    2x2 box filtering is performed when magnifying or reducing a texture, and a mipmap is picked from the list but no filtering is done between the levels of the mipmaps. This is equivalent to the complex format 'filtering linear linear point'.
292<DT>trilinear
293<DD>    2x2 box filtering is performed when magnifying and reducing a texture, and the closest 2 mipmaps are filtered together. This is equivalent to the complex format 'filtering linear linear linear'.
294<DT>anisotropic
295<DD>    This is the same as 'trilinear', except the filtering algorithm takes account of the slope of the triangle in relation to the camera rather than simply doing a 2x2 pixel filter in all cases. This makes triangles at acute angles look less fuzzy. Equivalent to the complex format 'filtering anisotropic anisotropic linear'. Note that in order for this to make any difference, you must also set the <A HREF="manual_17.html#SEC72">max_anisotropy</A> attribute too.
296</DL>
297<BR><BR>
298<STRONG>Complex Format</STRONG><BR>
299Format: filtering &#60;minification&#62; &#60;magnification&#62; &#60;mip&#62;<BR>
300Default: filtering linear linear point<BR><BR>
301This format gives you complete control over the minification, magnification, and mip filters. Each parameter can be one of the following:
302<DL COMPACT>
303<DT>none
304<DD>    Nothing - only a valid option for the 'mip' filter , since this turns mipmapping off completely. The lowest setting for min and mag is 'point'.
305<DT>point
306<DD>    Pick the closet pixel in min or mag modes. In mip mode, this picks the closet matching mipmap.
307<DT>linear
308<DD>    Filter a 2x2 box of pixels around the closest one. In the 'mip' filter this enables filtering between mipmap levels.
309<DT>anisotropic
310<DD>    Only valid for min and mag modes, makes the filter compensate for camera-space slope of the triangles. Note that in order for this to make any difference, you must also set the <A HREF="manual_17.html#SEC72">max_anisotropy</A> attribute too.
311</DL>
312<P>
313
314<A NAME="max_anisotropy"></A>
315<A NAME="SEC72"></A>
316<H3> max_anisotropy </H3>
317<!--docid::SEC72::-->
318<P>
319
320Sets the maximum degree of anisotropy that the renderer will try to compensate for when filtering textures. The degree of anisotropy is the ratio between the height of the texture segment visible in a screen space region versus the width - so for example a floor plane, which stretches on into the distance and thus the vertical texture coordinates change much faster than the horizontal ones, has a higher anisotropy than a wall which is facing you head on (which has an anisotropy of 1 if your line of sight is perfectly perpendicular to it). You should set the max_anisotropy value to something greater than 1 to begin compensating; higher values can compensate for more acute angles.<BR><BR>
321In order for this to be used, you have to set the minification and/or the magnification <A HREF="manual_17.html#SEC71">filtering</A> option on this texture to anisotropic.
322</P><P>
323
324Format: max_anisotropy &#60;value&#62;<BR>
325Default: max_anisotropy 1
326</P><P>
327
328<A NAME="colour_op"></A>
329<A NAME="SEC73"></A>
330<H3> colour_op </H3>
331<!--docid::SEC73::-->
332<P>
333
334Determines how the colour of this texture layer is combined with the one below it (or the lighting effect on the geometry if this is the first layer).<BR><BR>
335</P><P>
336
337Format: colour_op &#60;replace|add|modulate|alpha_blend&#62;<BR><BR>
338</P><P>
339
340This method is the simplest way to blend texture layers, because it requires only one parameter, gives you the most common blending types, and automatically sets up 2 blending methods: one for if single-pass multitexturing hardware is available, and another for if it is not and the blending must be achieved through multiple rendering passes. It is, however, quite limited and does not expose the more flexible multitexturing operations, simply because these can't be automatically supported in multipass fallback mode. If want to use the fancier options, use <A HREF="manual_17.html#SEC74">colour_op_ex</A>, but you'll either have to be sure that enough multitexturing units will be available, or you should explicitly set a fallback using <A HREF="manual_17.html#SEC75">colour_op_multipass_fallback</A>.<BR>
341<DL COMPACT>
342<DT>replace
343<DD>    Replace all colour with texture with no adjustment.
344<DT>add
345<DD>    Add colour components together.
346<DT>modulate
347<DD>    Multiply colour components together.
348<DT>alpha_blend
349<DD>    Blend based on texture alpha.
350</DL>
351<BR>
352Default: colour_op modulate
353<P>
354
355<A NAME="colour_op_ex"></A>
356<A NAME="SEC74"></A>
357<H3> colour_op_ex </H3>
358<!--docid::SEC74::-->
359<P>
360
361This is an extended version of the <A HREF="manual_17.html#SEC73">colour_op</A> attribute which allows extremely detailed control over the blending applied between this and earlier layers. Multitexturing hardware can apply more complex blending operations that multipass blendind, but you are limited to the number of texture units which are available in hardware.<BR><BR>
362</P><P>
363
364Format: colour_op_ex &#60;operation&#62; &#60;source1&#62; &#60;source2&#62; [&#60;manual_factor&#62;] [&#60;manual_colour1&#62;] [&#60;manual_colour2&#62;]<BR><BR>
365</P><P>
366
367Example colour_op_ex add_signed src_manual src_current 0.5<BR><BR>
368</P><P>
369
370See the IMPORTANT note below about the issues between mulitpass and multitexturing that using this method can create. Texture colour operations determine how the final colour of the surface appears when rendered. Texture units are used to combine colour values from various sources (e.g. the diffuse colour of the surface from lighting calculations, combined with the colour of the texture). This method allows you to specify the 'operation' to be used, i.e. the calculation such as adds or multiplies, and which values to use as arguments, such as a fixed value or a value from a previous calculation.<BR><BR>
371</P><P>
372
373<DL COMPACT>
374<DT>Operation options
375<DD><DL COMPACT>
376<DT>source1
377<DD>    Use source1 without modification
378<DT>source2
379<DD>    Use source2 without modification
380<DT>modulate
381<DD>    Multiply source1 and source2 together.
382<DT>modulate_x2
383<DD>    Multiply source1 and source2 together, then by 2 (brightening).
384<DT>modulate_x4
385<DD>    Multiply source1 and source2 together, then by 4 (brightening).
386<DT>add
387<DD>    Add source1 and source2 together.
388<DT>add_signed
389<DD>    Add source1 and source2 then subtract 0.5.
390<DT>add_smooth
391<DD>    Add source1 and source2, subtract the product
392<DT>subtract
393<DD>    Subtract source2 from source1
394<DT>blend_diffuse_alpha
395<DD>    Use interpolated alpha value from vertices to scale source1, then add source2 scaled by (1-alpha).
396<DT>blend_texture_alpha
397<DD>    As blend_diffuse_alpha but use alpha from texture
398<DT>blend_current_alpha
399<DD>    As blend_diffuse_alpha but use current alpha from previous stages (same as blend_diffuse_alpha for first layer)
400<DT>blend_manual
401<DD>    As blend_diffuse_alpha but use a constant manual alpha value specified in &#60;manual&#62;
402<DT>dotproduct
403<DD>    The dot product of source1 and source2
404<DT>blend_diffuse_colour
405<DD>    Use interpolated colour value from vertices to scale source1, then add source2 scaled by (1-colour).
406</DL>
407<DT>Source1 and source2 options
408<DD><DL COMPACT>
409<DT>src_current
410<DD>    The colour as built up from previous stages.
411<DT>src_texture
412<DD>    The colour derived from the texture assigned to this layer.
413<DT>src_diffuse
414<DD>    The interpolated diffuse colour from the vertices (same as 'src_current' for first layer).
415<DT>src_specular
416<DD>    The interpolated specular colour from the vertices.
417<DT>src_manual
418<DD>    The manual colour specified at the end of the command.
419</DL>
420</DL>
421<BR>
422For example 'modulate' takes the colour results of the previous layer, and multiplies them with the new texture being applied. Bear in mind that colours are RGB values from 0.0-1.0 so multiplying them together will result in values in the same range, 'tinted' by the multiply. Note however that a straight multiply normally has the effect of darkening the textures - for this reason there are brightening operations like modulate_x2. Note that because of the limitations on some underlying APIs (Direct3D included) the 'texture' argument can only be used as the first argument, not the second. <BR><BR>
423<P>
424
425Note that the last parameter is only required if you decide to pass a value manually into the operation. Hence you only need to fill these in if you use the 'blend_manual' operation.<BR><BR>
426</P><P>
427
428IMPORTANT: Ogre tries to use multitexturing hardware to blend texture layers together. However, if it runs out of texturing units (e.g. 2 of a GeForce2, 4 on a GeForce3) it has to fall back on multipass rendering, i.e. rendering the same object multiple times with different textures. This is both less efficient and there is a smaller range of blending operations which can be performed. For this reason, if you use this method you really should set the colour_op_multipass_fallback attribute to specify which effect you want to fall back on if sufficient hardware is not available (the default is just 'modulate' which is unlikely to be what you want if you're doing swanky blending here). If you wish to avoid having to do this, use the simpler colour_op attribute which allows less flexible blending options but sets up the multipass fallback automatically, since it only allows operations which have direct multipass equivalents.<BR><BR>
429</P><P>
430
431Default: none (colour_op modulate)<BR>
432</P><P>
433
434<A NAME="colour_op_multipass_fallback"></A>
435<A NAME="SEC75"></A>
436<H3> colour_op_multipass_fallback </H3>
437<!--docid::SEC75::-->
438<P>
439
440Sets the multipass fallback operation for this layer, if you used colour_op_ex and not enough multitexturing hardware is available.<BR><BR>
441</P><P>
442
443Format: colour_op_multipass_fallback &#60;src_factor&#62; &#60;dest_factor&#62;<BR><BR>
444</P><P>
445
446Example: colour_op_mulitpass_fallback one one_minus_dest_alpha<BR><BR>
447</P><P>
448
449Because some of the effects you can create using colour_op_ex are only supported under multitexturing hardware, if the hardware is lacking the system must fallback on multipass rendering, which unfortunately doesn't support as many effects. This attribute is for you to specify the fallback operation which most suits you.<BR><BR>
450</P><P>
451
452The parameters are the same as in the scene_blend attribute; this is because multipass rendering IS effectively scene blending, since each layer is rendered on top of the last using the same mechanism as making an object transparent, it's just being rendered in the same place repeatedly to get the multitexture effect. If you use the simpler (and less flexible) colour_op attribute you don't need to call this as the system sets up the fallback for you.<BR><BR>
453</P><P>
454
455<A NAME="alpha_op_ex"></A>
456<A NAME="SEC76"></A>
457<H3> alpha_op_ex </H3>
458<!--docid::SEC76::-->
459<P>
460
461Behaves in exactly the same away as <A HREF="manual_17.html#SEC74">colour_op_ex</A> except that it determines how alpha values are combined between texture layers rather than colour values.The only difference is that the 2 manual colours at the end of colour_op_ex are just single floating-point values in alpha_op_ex.
462</P><P>
463
464<A NAME="env_map"></A>
465<A NAME="SEC77"></A>
466<H3> env_map </H3>
467<!--docid::SEC77::-->
468<P>
469
470Turns on/off texture coordinate effect that makes this layer an environment map.<BR><BR>
471</P><P>
472
473Format: env_map &#60;off|spherical|planar|cubic_reflection|cubic_normal&#62;<BR><BR>
474</P><P>
475
476Environment maps make an object look reflective by using automatic texture coordinate generation depending on the relationship between the objects vertices or normals and the eye.<BR><BR>
477<DL COMPACT>
478<DT>spherical
479<DD>    A spherical environment map. Requires a single texture which is either a fish-eye lens view of the reflected scene, or some other texture which looks good as a spherical map (a texture of glossy highlights is popular especially in car sims). This effect is based on the relationship between the eye direction and the vertex normals of the object, so works best when there are a lot of gradually changing normals, i.e. curved objects.
480<DT>planar
481<DD>    Similar to the spherical environment map, but the effect is based on the position of the vertices in the viewport rather than vertex normals. This effect is therefore useful for planar geometry (where a spherical env_map would not look good because the normals are all the same) or objects without normals.
482<DT>cubic_reflection
483<DD>    A more advanced form of reflection mapping which uses a group of 6 textures making up the inside of a cube, each of which is a view if the scene down each axis. Works extremely well in all cases but has a higher technical requirement from the card than spherical mapping. Requires that you bind a <A HREF="manual_17.html#SEC67">cubic_texture</A> to this texture unit and use the 'combinedUVW' option.
484<DT>cubic_normal
485<DD>    Generates 3D texture coordinates containing the camera space normal vector from the normal information held in the vertex data. Again, full use of this feature requires a <A HREF="manual_17.html#SEC67">cubic_texture</A> with the 'combinedUVW' option.
486       
487</DL>
488<BR>
489Default: env_map off<BR>
490<P>
491
492<A NAME="scroll"></A>
493<A NAME="SEC78"></A>
494<H3> scroll </H3>
495<!--docid::SEC78::-->
496<P>
497
498Sets a fixed scroll offset for the texture.<BR><BR>
499</P><P>
500
501Format: scroll &#60;x&#62; &#60;y&#62;<BR><BR>
502</P><P>
503
504This method offsets the texture in this layer by a fixed amount. Useful for small adjustments without altering texture coordinates in models. However if you wish to have an animated scroll effect, see the <A HREF="manual_17.html#SEC79">scroll_anim</A> attribute.<BR><BR>
505</P><P>
506
507<A NAME="scroll_anim"></A>
508<A NAME="SEC79"></A>
509<H3> scroll_anim </H3>
510<!--docid::SEC79::-->
511<P>
512
513Sets up an animated scroll for the texture layer. Useful for creating fixed-speed scrolling effects on a texture layer (for varying scroll speeds, see <A HREF="manual_17.html#SEC83">wave_xform</A>).<BR><BR>
514</P><P>
515
516Format: scroll_anim &#60;xspeed&#62; &#60;yspeed&#62;<BR>
517</P><P>
518
519<A NAME="rotate"></A>
520<A NAME="SEC80"></A>
521<H3> rotate </H3>
522<!--docid::SEC80::-->
523<P>
524
525Rotates a texture to a fixed angle. This attribute changes the rotational orientation of a texture to a fixed angle, useful for fixed adjustments. If you wish to animate the rotation, see <A HREF="manual_17.html#SEC81">rotate_anim</A>.<BR><BR>
526</P><P>
527
528Format: rotate &#60;angle&#62;<BR><BR>
529</P><P>
530
531The parameter is a anticlockwise angle in degrees.<BR><BR>
532</P><P>
533
534<A NAME="rotate_anim"></A>
535<A NAME="SEC81"></A>
536<H3> rotate_anim </H3>
537<!--docid::SEC81::-->
538<P>
539
540Sets up an animated rotation effect of this layer. Useful for creating fixed-speed rotation animations (for varying speeds, see <A HREF="manual_17.html#SEC83">wave_xform</A>).<BR><BR>
541</P><P>
542
543Format: rotate_anim &#60;revs_per_second&#62;<BR><BR>
544</P><P>
545
546The parameter is a number of anticlockwise revolutions per second.<BR><BR>
547</P><P>
548
549<A NAME="scale"></A>
550<A NAME="SEC82"></A>
551<H3> scale </H3>
552<!--docid::SEC82::-->
553<P>
554
555Adjusts the scaling factor applied to this texture layer. Useful for adjusting the size of textures without making changes to geometry. This is a fixed scaling factor, if you wish to animate this see <A HREF="manual_17.html#SEC83">wave_xform</A>.<BR><BR>
556</P><P>
557
558Format: scale &#60;x_scale&#62; &#60;y_scale&#62;<BR><BR>
559</P><P>
560
561Valid scale values are greater than 0, with a scale factor of 2 making the texture twice as big in that dimension etc.<BR><BR>
562</P><P>
563
564<A NAME="wave_xform"></A>
565<A NAME="SEC83"></A>
566<H3> wave_xform </H3>
567<!--docid::SEC83::-->
568<P>
569
570Sets up a transformation animation based on a wave function. Useful for more advanced texture layer transform effects. You can add multiple instances of this attribute to a single texture layer if you wish.<BR><BR>
571</P><P>
572
573Format: wave_xform &#60;xform_type&#62; &#60;wave_type&#62; &#60;base&#62; &#60;frequency&#62; &#60;phase&#62; &#60;amplitude&#62;<BR><BR>
574</P><P>
575
576Example: wave_xform scale_x sine 1.0 0.2 0.0 5.0<BR><BR>
577<DL COMPACT>
578<DT>xform_type
579<DD><DL COMPACT>
580<DT>scroll_x
581<DD>    Animate the x scroll value
582<DT>scroll_y
583<DD>    Animate the y scroll value
584<DT>rotate
585<DD>    Animate the rotate value
586<DT>scale_x
587<DD>    Animate the x scale value
588<DT>scale_y
589<DD>    Animate the y scale value
590</DL>
591<DT>wave_type
592<DD><DL COMPACT>
593<DT>sine
594<DD>    A typical sine wave which smoothly loops between min and max values
595<DT>triangle
596<DD>    An angled wave which increases &#38; decreases at constant speed, changing instantly at the extremes
597<DT>square
598<DD>    Max for half the wavelength, min for the rest with instant transition between
599<DT>sawtooth
600<DD>    Gradual steady increase from min to max over the period with an instant return to min at the end.
601<DT>inverse_sawtooth
602<DD>    Gradual steady decrease from max to min over the period, with an instant return to max at the end.
603</DL>
604<DT>base
605<DD>    The base value, the minimum if amplitude &#62; 0, the maximum if amplitdue &#60; 0
606<DT>frequency
607<DD>    The number of wave iterations per second, i.e. speed
608<DT>phase
609<DD>    Offset of the wave start
610<DT>amplitude
611<DD>    The size of the wave
612</DL>
613<BR>
614The range of the output of the wave will be {base, base+amplitude}. So the example above scales the texture in the x direction between 1 (normal size) and 5 along a sine wave at one cycle every 5 second (0.2 waves per second).<BR><BR>
615<P>
616
617<A NAME="transform"></A>
618<A NAME="SEC84"></A>
619<H3> transform </H3>
620<!--docid::SEC84::-->
621<P>
622
623This attribute allows you to specify a static 4x4 transformation matrix for the texture unit, thus replacing the individual scroll, rotate and scale attributes mentioned above. <BR><BR>
624</P><P>
625
626Format: transform m00 m01 m02 m03 m10 m11 m12 m13 m20 m21 m22 m23 m30 m31 m32 m33<BR><BR>
627</P><P>
628
629The indexes of the 4x4 matrix value above are expressed as m&#60;row&#62;&#60;col&#62;.
630</P><P>
631
632<A NAME="Declaring Vertex and Fragment Programs"></A>
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