Created attachment 45121 [details]
terminal output

There is a strange triangle of whiter area and missing effects between screen center and horizon in Oilrush.

I'm attaching terminal output, however I don't think there is anything important, just a few of: 

Mesa warning: glDraw[Range]Elements(start 130, end 877, count 1650, type 0x1403, indices=0x1c2)
	end is out of bounds (max=876)  Element Buffer 31 (size 3750)
	This should probably be fixed in the application.
and 

Mesa: User error: GL_INVALID_VALUE in glTexSubImage2D(xoffset+width)
OpenGL error: invalid value

However both of those errors are also present with llvmpipe which renders fine (not 100% fine, but this bug is not present there). 
RADEON_NOT_TCL=1 also solves this issue, where READEON_DEBUG=noopt has no effect.

BTW you need to set MESA_EXTENSION_OVERRIDE="-GL_ARB_draw_instanced" when using llvmpipe of software TCL otherwise you run into other troubles like: 

GLShader::loadVertex(): error in "core/shaders/default/meshes/vertex_base.shader" file
defines: UNKNOWN,QUALITY_LOW,MULTISAMPLE_0,USE_INSTANCING,USE_TEXTURE_3D,USE_ALPHA_FADE,USE_ENVIRONMENT,OPENGL,USE_PSEUDO_INSTANCING,USE_PSEUDO_TRANSFORM,HAS_ARB_DRAW_INSTANCED,BASE_AMBIENT_REFLECTION_CUBE,AMBIENT,PAINT,OPACITY,MULTIPLY_0
0:194(39): error: `gl_InstanceID' undeclared
0:194(42): error: Operands to arithmetic operators must be numeric
0:194(19): error: cannot construct `ivec3' from a non-numeric data type
0:194(58): error: Operands to arithmetic operators must be numeric

and almost no rendering at all.

My system
GPU:RV530
mesa: 9f013a8233197d4a0482661cb37cfeac1a61b804
Kernel: 2.6.38

Oilrush version: 0.61