How to Add a Background Image for Render (Backbuf) in Blender 2.5
In the previous tutorials, we created 3d text and added some lights, specularity to material, etc. We also changed the color of the background to black. But how about adding a background image* to your scene? That would make your 3d text appear over the image when you render.
In the properties window, go to the texture panel. There are three subpanels, with tooltips - 'Show Material Textures', 'Show World Textures' and 'Show brush Textures'. Click on the second subpanel, which World Textures.
Click on "+ New" button to add a new texture. In the Type, select image or movie. In the Image section click on Open, and select** your image. Down in the "Influence", enable Horizon by clicking on the checkbox.
We have selected a texture for the world so instead of the plain color it was earlier showing in the background, now a texture would be displayed. Since we've selected the texture type to be image, the image would be shown in the background. However, we have to tell Blender 2.5, what the image would influence. In this case, since we want the entire horizon to be influenced, we've enabled that.
Render your image. It might not be properly aligned. Just check the resolution of the image and set the same resolution for your render. To do that, go to the "Render" Panel in the Properties window - (first panel). In the "Dimensions" section, enter x and y co-ordinates of the background image.
Go back to the "World" Panel, and enable Paper sky in "World" Section.
In the 3d Viewport, go to camera view (NUMPAD 0***), and make sure that your text in inside the camera frame. Scale it down**** (S Key) if required, or you could also zoom out in the camera view****. Position the text in the desired manner.
Take a render and you should see your 3d text displayed properly over your image. Save**** the rendered image. This technique can be used to add an interesting background image to any of your projects.
*The feature "Render Backbuf Image" in enlisted in "Dropped Features" in the miscellaneous section on Blender 2.5 Development Status wiki page since it was rather superfluous - you can get the background image using the above steps.
** If you want Preview of the images to be shown in file browser, click on "Display Files as Thumbnails" - this is the third button in the panel next to "Create New Directory" at the top of the file browser.
*** Command is already discussed in detail in previous blender 2.5 tutorial on creating 3d text
**** Commands are already discussed in detail in second part of Blender 2.5 3d text tutorial