blitz3d/_release/tutorials/GCUK_Tuts/page5.html

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<h1 align="left"><font color="#FFFFFF">&nbsp;Texturing</font></h1>
<p align="left"><b>&nbsp;Aim</b>: How to texture an object<br>
&nbsp;<b>Skill level</b>: Intermediate<br>
&nbsp;<b>Files Needed</b>: texture.bb / blitztexture.bmp
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<img src="7c.jpg" alt="Texturing" width="166" height="127">
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<p>
For our objects to look more realistic we really need to texture them, but what is texture mapping ?<br>
Think if it as a way of adding extra details to an object. For example... You design an ordinary white cube, doesn't look much does it ?</p>
<p>
But add a texturemap to it, and suddenly you have a BORG cube !.<br>
Textures are bitmap pictures that have been designed with a paint program (that can save BMP format files.)</p>
<p>
Another example... If you designed a basic model of a creature, using a texturemap you could add all the external features - such as clothes and facial expressions.</p>
<p>
Although B3D has alot of commands to manage multiple textures and special effects, for now we shall just be using the very basic EntityTexture command.<br>

Of course we could save ourselves alot of time by designing our objects and applying the textures to them directly from a 3d modelling program, but that would make this tutorial a waste of time !.<br><br>

So why would we want to apply a texture in realtime ?, well for starters a new texture may be put onto the object at any time. Take a wall, shoot it ! - now for things to look realistic in our 3d world, we would like to have somekind of indication that it was shot. We could do this by loading a texture of a bullet hole directly onto the wall. Every 3d game currently on the market uses texture trickery in some form or another, as your experience grows - so will your imagination !. Why have a flat river, when you could use texturemaps to give the impression of ripples or waves.</p>

<p>B3D has so many lovely features for us to use including the new ANIMATED textures command, we will be using this later on !. (Quake I/II/III used this trick to give us the impression of moving water)</p>

<p>Let's look at this in practice:</p>

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      &nbsp; <font face="arial">Graphics3D 800,600<br>
      <br>
      &nbsp; SetBuffer BackBuffer()<br>
      <br>
      &nbsp; camera=CreateCamera()<br>
      &nbsp; CameraViewport camera,0,0,800,600<br>
      <br>
      &nbsp; light=CreateLight()<br>
      <br>
	  &nbsp; cube=CreateCube()<br>
	  &nbsp; PositionEntity cube,0,0,5<br>
	  
	  
	  <br>
      &nbsp; texture=LoadTexture("blitztexture.bmp")<br>
      &nbsp; EntityTexture cube,texture<br>
      <br>
      &nbsp; While Not KeyHit(1)<br>
      <br>
	  &nbsp; TurnEntity cube,0.1,0.2,0.3<br>      
      <br>
      &nbsp; UpdateWorld<br>
      &nbsp; RenderWorld<br>
      <br>
      &nbsp; Text 340,500,&quot;Texturing Demo&quot;<br>
      <br>
      &nbsp; Flip<br>
      <br>
      &nbsp; Wend<br>
      &nbsp; End<br><br>
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<p>
As you can see, a texture can make all the difference to a very basic object.</p> 
<p>
The only 2 lines of code we don't already know are:
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<font face="Arial">texture=LoadTexture(&quot;blitztexture.bmp&quot;)<br>
EntityTexture cube,texture</font></b>
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<p>
Two nice and friendly commands, the first loads a texturemap into memory - with the pointer variable 'texture' pointing to it.<br><br>

Once we have successfully loaded the texture, we assign it to the object using the <b>EntityTexture</b> command. (here we are assigning the variable pointer TEXTURE to the cube we defined earlier)<br><br>

You could if you wanted load the picture file <b>BLITZTEXTURE.BMP</b> into MS Paint and make some changes.. if you wanted to !<br><br>

And that's all there is to it, but a quick word of advice: If your object isn't textured as it should, always check that the texturemaps are in the right directory. It's all to easy to spend half the day trying to work out a texturing problem, only to find that you moved the program to another directory without dragging the associated texture files with it.
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<center><font color="#808080">Tutorial 5 - <a href="page6.html">Lighting</a></font></center></font>