glColorMaterial()'s bug ?

Hi there,

I work on a project with OpenGL and SDL. When I use:
to set the material properties automatically when I issue glColor*(), it doesnt seem to function correctly.

My scene is composed of a world with GL_LIGHT0 activated and a GUI drawn without any light. Of course, I disable GL_LIGHT0, GL_COLOR_MATERIAL and GL_LIGHTING when I draw the GUI. However the last glColor*() I use to draw the GUI modifies the properties of GL_LIGHT0 or/and the material properties. My world which is drawn before the GUI is lighted with the color I set when I draw the GUI after the world.

However, when I replace the
by “many” calls to
everything works well.

I don’t know if it’s whether driver’s bug or the kernel’s bug or the XFree’s.
Please help !

Here is a screenshot of the world and the GUI (without any light enabled)

Development platform:
Linux 2.4.22, gcc-3.3.1 (GCC) 3.3.1 (Mandrake Linux 9.2 3.3.1-2mdk)

Model: Medion Microstar laptop computer
Processor: P-IV 2.4 GHz - 768 Mb RAM
OS: Linux 2.4.22 - 256 Mb swap; WinXP - 1Gb swap
Patches: drm, fb (mdk for Linux)
Soundcard: SiS SI7012 (driver intel8x0 with ALSA)
Videocard: ATI Radeon 9000 M - 64 Mb
Resolution: 1024x768
DVD/CDR/RW drive

SDL version 1.2.5

GL Vendor: ‘Tungsten Graphics, Inc.’
GL Renderer: ‘Mesa DRI R200 20020827 AGP 4x x86/MMX/SSE TCL’
GL Version: ‘1.2 Mesa 4.0.4’
GL Extensions: ‘GL_ARB_imaging GL_ARB_multitexture GL_ARB_texture_env_add GL_ARB_texture_env_combine GL_ARB_texture_env_dot3 GL_ARB_transpose_matrix GL_EXT_abgr GL_EXT_bgra GL_EXT_blend_color GL_EXT_blend_logic_op GL_EXT_blend_minmax GL_EXT_blend_subtract GL_EXT_clip_volume_hint GL_EXT_convolution GL_EXT_compiled_vertex_array GL_EXT_histogram GL_EXT_packed_pixels GL_EXT_polygon_offset GL_EXT_rescale_normal GL_EXT_secondary_color GL_EXT_stencil_wrap GL_EXT_texture3D GL_EXT_texture_env_add GL_EXT_texture_env_combine GL_EXT_texture_env_dot3 GL_EXT_texture_filter_anisotropic GL_EXT_texture_object GL_EXT_texture_lod_bias GL_EXT_vertex_array GL_IBM_rasterpos_clip GL_MESA_pack_invert GL_MESA_ycbcr_texture GL_MESA_window_pos GL_NV_texgen_reflection GL_NV_texture_rectangle GL_SGI_color_matrix GL_SGI_color_table’

XFree86 Version 4.3.0
Release Date: 9 May 2003
X Protocol Version 11, Revision 0, Release 6.6
Build Operating System: Linux 2.4.18-23mdksmp i686 [ELF]
Build Date: 10 September 2003
Before reporting problems, check http://www.XFree86.Org/
to make sure that you have the latest version.
Module Loader present

I don’t think its a bug, its actually the intended behavior of glColorMaterial.
Look at #14,
if I understand you correctly this is what is happening

Hi there,

Thank you for your answer but it’s not the problem of glColorMaterial() and glEnable()'s orders. My problem can be represented by this listing:

void display(void)
	glEnable( GL_LIGHTING );
	glEnable( GL_LIGHT0 );

	glColor4ub( 255, 0, 0, 255 );	//red
	glBegin( GL_TRIANGLES );
		// some vertices here

	glDisable( GL_LIGHTING );
	glDisable( GL_LIGHT0 );
	glDisable( GL_COLOR_MATERIAL );



void renderGUI(void)
	glColor4ub( 0, 255, 0, 255 );	//green
	glBegin( GL_QUADS );
		// some vertices here

Let’s say, in the main loop, I call display() every 50ms. At the first call, I have the triangles rendered in RED as expected. But from the second call and so on, the triangles are drawn with a blended color between RED and GREEN.

Another solution that I’ve found is to insert a call to glColor as

glColor4ub( 255, 255, 255, 255 );

before I call


So can you tell me why ? If you want more informations on my project, don’t hesitate to ask.