Bug 186

Summary: Incorrect mipmap images with gluBuild2DMipmaps
Product: [JogAmp] Jogl Reporter: Sven Gothel <sgothel>
Component: coreAssignee: Sven Gothel <sgothel>
Status: VERIFIED FIXED    
Severity: normal    
Priority: P3    
Version: 1   
Hardware: All   
OS: all   
Type: DEFECT SCM Refs:
Workaround: ---
Attachments: Program showing the difference between two mipmap methods

Description Sven Gothel 2010-03-24 07:48:12 CET


---- Reported by jzwiers 2005-12-16 10:11:28 ----

When using gluBuild2DMipmaps, some textures show artefacts for certain 
distances. These artefacts do no occur when using auto-generated mipmaps, 
produced by setting GL_GENERATE_MIPMAP to true. The artefacts themselves 
disappear when setting -Djogl.glu.nojava, but the mipmap levels are still 
slighly different from those produced by the GL_GENERATE_MIPMAP method.
The example program shows some "chromic"texture that has a reddish glow at 
certain areas, when using gluBuild2DMipmaps. When using a "Grass"area, there 
are black stripes, when viewing from certain angles.



---- Additional Comments From jzwiers 2005-12-16 10:16:30 ----

Created an attachment
Program showing the difference between two mipmap methods




---- Additional Comments From kbr 2005-12-31 16:09:37 ----

This was a bug in the port from SGI's C code in gluBuild2DMipmapLevelsCore in
the case where the unpack alignment was greater than the row width of the mipmap
level. The fix will show up in the next nightly build (when they are re-enabled
after the holiday break) and in JSR-231 beta 2.

It is not surprising that the mipmaps generated by GLU differ slightly from
those generated automatically with the new GL_GENERATE_MIPMAP method. There is
no precise specification of the GLU library's mipmap results.




--- Bug imported by sgothel@jausoft.com 2010-03-24 07:48 EDT  ---

This bug was previously known as _bug_ 186 at https://jogl.dev.java.net/bugs/show_bug.cgi?id=186
Imported an attachment (id=67)

The original submitter of attachment 67 [details] is unknown.
   Reassigning to the person who moved it here: sgothel@jausoft.com.