C++ qglDisableClientState函数代码示例

/*
================
DrawTris

Draws triangle outlines for debugging
================
*/
static void DrawTris (shaderCommands_t *input) {
	GL_Bind( tr.whiteImage );
	qglColor3f (1,1,1);

	GL_State( GLS_POLYMODE_LINE | GLS_DEPTHMASK_TRUE );
	qglDepthRange( 0, 0 );

	qglDisableClientState (GL_COLOR_ARRAY);
	qglDisableClientState (GL_TEXTURE_COORD_ARRAY);

	qglVertexPointer (3, GL_FLOAT, 16, input->xyz);	// padded for SIMD

	if (qglLockArraysEXT) {
		qglLockArraysEXT(0, input->numVertexes);
		GLimp_LogComment( "glLockArraysEXT\n" );
	}

	#ifdef HAVE_GLES
	qglDrawElements( GL_LINE_STRIP, 
					input->numIndexes,
					GL_INDEX_TYPE,
					input->indexes );
	#else
	R_DrawElements( input->numIndexes, input->indexes );
	#endif

	if (qglUnlockArraysEXT) {
		qglUnlockArraysEXT();
		GLimp_LogComment( "glUnlockArraysEXT\n" );
	}
	qglDepthRange( 0, 1 );
}

static void DrawSkySide( struct image_s *image, const int mins[2], const int maxs[2] )
{
	int s, t;

	GL_Bind( image );
	#ifdef HAVE_GLES
	GLfloat vtx[3*1024];	// arbitrary sized
	GLfloat tex[2*1024];
	int idx;
	
	GLboolean text = qglIsEnabled(GL_TEXTURE_COORD_ARRAY);
	GLboolean glcol = qglIsEnabled(GL_COLOR_ARRAY);
	if (glcol)
		qglDisableClientState(GL_COLOR_ARRAY);
	if (!text)
		qglEnableClientState( GL_TEXTURE_COORD_ARRAY );
	#endif

	for ( t = mins[1]+HALF_SKY_SUBDIVISIONS; t < maxs[1]+HALF_SKY_SUBDIVISIONS; t++ )
	{
#ifdef HAVE_GLES
		idx=0;
#else
		qglBegin( GL_TRIANGLE_STRIP );
#endif

		for ( s = mins[0]+HALF_SKY_SUBDIVISIONS; s <= maxs[0]+HALF_SKY_SUBDIVISIONS; s++ )
		{
			#ifdef HAVE_GLES
			memcpy(tex+idx*2, s_skyTexCoords[t][s], sizeof(GLfloat)*2);
			memcpy(vtx+idx*3, s_skyPoints[t][s], sizeof(GLfloat)*3);
			idx++;
			memcpy(tex+idx*2, s_skyTexCoords[t+1][s], sizeof(GLfloat)*2);
			memcpy(vtx+idx*3, s_skyPoints[t+1][s], sizeof(GLfloat)*3);
			idx++;
			#else
			qglTexCoord2fv( s_skyTexCoords[t][s] );
			qglVertex3fv( s_skyPoints[t][s] );

			qglTexCoord2fv( s_skyTexCoords[t+1][s] );
			qglVertex3fv( s_skyPoints[t+1][s] );
			#endif
		}

		#ifdef HAVE_GLES
		//*TODO* Try to switch from many DrawArrays of GL_TRIANGLE_STRIP to a single DrawArrays of TRIANGLES to see if it perform better
		qglVertexPointer (3, GL_FLOAT, 0, vtx);
		qglTexCoordPointer(2, GL_FLOAT, 0, tex);
		qglDrawArrays(GL_TRIANGLE_STRIP, 0, idx);
		#else
		qglEnd();
		#endif
	}
	#ifdef HAVE_GLES
	if (glcol)
		qglEnableClientState(GL_COLOR_ARRAY);
	if (!text)
		qglDisableClientState( GL_TEXTURE_COORD_ARRAY );
	#endif
}

//DRAWCEL
static void DrawCel (shaderCommands_t *input) {

	GL_Bind( tr.whiteImage );
	qglColor3f (1,1,1);

	GL_State( GLS_POLYMODE_LINE | GLS_DEPTHMASK_TRUE );

	qglDisableClientState (GL_COLOR_ARRAY);
	qglDisableClientState (GL_TEXTURE_COORD_ARRAY);

	qglVertexPointer (3, GL_FLOAT, 16, input->xyz);	// padded for SIMD

	if (qglLockArraysEXT) {
		qglLockArraysEXT(0, input->numVertexes);
		GLimp_LogComment( "glLockArraysEXT\n" );
	}

	R_DrawCel( input->numIndexes, input->indexes );

	if (qglUnlockArraysEXT) {
		qglUnlockArraysEXT();
		GLimp_LogComment( "glUnlockArraysEXT\n" );
	}

}

/*
==================
RB_NV20_DI_DiffuseColorPass

==================
*/
static void RB_NV20_DI_DiffuseColorPass(const drawInteraction_t *din)
{
	RB_LogComment("---------- RB_NV20_DiffuseColorPass ----------\n");

	GL_State(GLS_SRCBLEND_DST_ALPHA | GLS_DSTBLEND_ONE | GLS_DEPTHMASK | GLS_ALPHAMASK
	         | backEnd.depthFunc);

	// texture 0 will be the per-surface diffuse map
#ifdef MACOS_X
	GL_SelectTexture(0);
	qglEnableClientState(GL_TEXTURE_COORD_ARRAY);
#else
	GL_SelectTextureNoClient(0);
#endif
	din->diffuseImage->Bind();

	// texture 1 will be the light projected texture
#ifdef MACOS_X
	GL_SelectTexture(1);
	qglEnableClientState(GL_TEXTURE_COORD_ARRAY);
#else
	GL_SelectTextureNoClient(1);
#endif
	din->lightImage->Bind();

	// texture 2 is disabled
#ifdef MACOS_X
	GL_SelectTexture(2);
	qglDisableClientState(GL_TEXTURE_COORD_ARRAY);
#else
	GL_SelectTextureNoClient(2);
#endif
	globalImages->BindNull();

	// texture 3 is disabled
#ifdef MACOS_X
	GL_SelectTexture(3);
	qglDisableClientState(GL_TEXTURE_COORD_ARRAY);
#else
	GL_SelectTextureNoClient(3);
#endif
	globalImages->BindNull();

	// bind our "fragment program"
	RB_NV20_DiffuseColorFragment();

	// override one parameter for inverted vertex color
	if (din->vertexColor == SVC_INVERSE_MODULATE) {
		qglCombinerInputNV(GL_COMBINER0_NV, GL_RGB, GL_VARIABLE_B_NV,
		                   GL_PRIMARY_COLOR_NV, GL_UNSIGNED_INVERT_NV, GL_RGB);
	}

	// draw it
	qglBindProgramARB(GL_VERTEX_PROGRAM_ARB, VPROG_NV20_DIFFUSE_COLOR);
	RB_DrawElementsWithCounters(din->surf->geo);
}

/*
=================
RB_ShadowFinish

Darken everything that is is a shadow volume.
We have to delay this until everything has been shadowed,
because otherwise shadows from different body parts would
overlap and double darken.
=================
*/
void RB_ShadowFinish(void)
{
	if (r_shadows->integer != 2)
	{
		return;
	}
	if (glConfig.stencilBits < 4)
	{
		return;
	}
	qglEnable(GL_STENCIL_TEST);
	qglStencilFunc(GL_NOTEQUAL, 0, 255);

	qglDisable(GL_CLIP_PLANE0);
	qglDisable(GL_CULL_FACE);

	GL_Bind(tr.whiteImage);

	qglLoadIdentity();

	qglColor3f(0.6f, 0.6f, 0.6f);
	GL_State(GLS_DEPTHMASK_TRUE | GLS_SRCBLEND_DST_COLOR | GLS_DSTBLEND_ZERO);

	GLboolean text  = qglIsEnabled(GL_TEXTURE_COORD_ARRAY);
	GLboolean glcol = qglIsEnabled(GL_COLOR_ARRAY);
	if (text)
	{
		qglDisableClientState(GL_TEXTURE_COORD_ARRAY);
	}
	if (glcol)
	{
		qglDisableClientState(GL_COLOR_ARRAY);
	}
	GLfloat vtx[] =
	{
		-100, 100,  -10,
		100,  100,  -10,
		100,  -100, -10,
		-100, -100, -10
	};
	qglVertexPointer(3, GL_FLOAT, 0, vtx);
	qglDrawArrays(GL_TRIANGLE_FAN, 0, 4);
	if (text)
	{
		qglEnableClientState(GL_TEXTURE_COORD_ARRAY);
	}
	if (glcol)
	{
		qglEnableClientState(GL_COLOR_ARRAY);
	}

	qglColor4f(1, 1, 1, 1);
	qglDisable(GL_STENCIL_TEST);
}

static void DrawSkySide( struct image_s *image, const int mins[2], const int maxs[2] )
{
	int s, t, i = 0;
	int size;
	glIndex_t *indicies;

	size = (maxs[1] - mins[1]) * (maxs[0] - mins[0] + 1);
	indicies = ri.Hunk_AllocateTempMemory(sizeof(glIndex_t) * size);

	GL_Bind( image );

	for ( t = mins[1]+HALF_SKY_SUBDIVISIONS; t < maxs[1]+HALF_SKY_SUBDIVISIONS; t++ )
	{
		for ( s = mins[0]+HALF_SKY_SUBDIVISIONS; s <= maxs[0]+HALF_SKY_SUBDIVISIONS; s++ )
		{
			indicies[i++] = t * (SKY_SUBDIVISIONS + 1) + s;
			indicies[i++] = (t + 1) * (SKY_SUBDIVISIONS + 1) + s;
		}
	}

	qglDisableClientState(GL_COLOR_ARRAY);
	qglEnableClientState(GL_TEXTURE_COORD_ARRAY);
	qglTexCoordPointer(2, GL_FLOAT, 0, s_skyTexCoords);
	qglVertexPointer(3, GL_FLOAT, 0, s_skyPoints);
	qglDrawElements(GL_TRIANGLE_STRIP, i, GL_INDEX_TYPE, indicies);
	Hunk_FreeTempMemory(indicies);
}

/*
======================
RB_FinishStageTexture
======================
*/
void RB_FinishStageTexture( const textureStage_t *texture, const drawSurf_t *surf ) {
	if ( texture->texgen == TG_DIFFUSE_CUBE || texture->texgen == TG_SKYBOX_CUBE 
		|| texture->texgen == TG_WOBBLESKY_CUBE ) {
		qglTexCoordPointer( 2, GL_FLOAT, sizeof( idDrawVert ), 
			(void *)&(((idDrawVert *)vertexCache.Position( surf->geo->ambientCache ))->st) );
	}

	if ( texture->texgen == TG_REFLECT_CUBE ) {
		qglDisable( GL_TEXTURE_GEN_S );
		qglDisable( GL_TEXTURE_GEN_T );
		qglDisable( GL_TEXTURE_GEN_R );
		qglTexGenf( GL_S, GL_TEXTURE_GEN_MODE, GL_OBJECT_LINEAR );
		qglTexGenf( GL_T, GL_TEXTURE_GEN_MODE, GL_OBJECT_LINEAR );
		qglTexGenf( GL_R, GL_TEXTURE_GEN_MODE, GL_OBJECT_LINEAR );
		qglDisableClientState( GL_NORMAL_ARRAY );

		qglMatrixMode( GL_TEXTURE );
		qglLoadIdentity();
		qglMatrixMode( GL_MODELVIEW );
	}

	if ( texture->hasMatrix ) {
		qglMatrixMode( GL_TEXTURE );
		qglLoadIdentity();
		qglMatrixMode( GL_MODELVIEW );
	}
}

/*
=============
RB_DrawMeshTris
Re-draws a mesh in outline mode
=============
*/
void RB_DrawMeshTris (void)
{
	int i, numTMUs = 0;

	if (!r_showtris->value)
		return;

	if (r_showtris->value == 1)
		GL_Disable(GL_DEPTH_TEST);

	qglPolygonMode (GL_FRONT_AND_BACK, GL_LINE);
	for (i=0; i<glConfig.max_texunits; i++)
		if (glState.activetmu[i])
		{	numTMUs++;		GL_DisableTexture (i);	}
	qglDisableClientState (GL_COLOR_ARRAY);
	qglColor4f(1.0, 1.0, 1.0, 1.0);

	RB_DrawArrays ();

	qglEnableClientState (GL_COLOR_ARRAY);
	for (i=0; i<numTMUs; i++)
		GL_EnableTexture(i);
	qglPolygonMode (GL_FRONT_AND_BACK, GL_FILL);

	if (r_showtris->value == 1)
		GL_Enable(GL_DEPTH_TEST);
}

/*
=============
RB_DrawMeshTris
Re-draws a mesh in outline mode
=============
*/
void RB_DrawMeshTris (GLenum polyMode, int numTMUs)
{
	int i;

	if (!r_showtris->value)
		return;

	if (r_showtris->value == 1)
		GL_Disable(GL_DEPTH_TEST);

	qglPolygonMode (GL_FRONT_AND_BACK, GL_LINE);
	for (i=0; i<numTMUs; i++)
		GL_DisableTexture (i);
	qglDisableClientState (GL_COLOR_ARRAY);
	qglColor4f(1.0, 1.0, 1.0, 1.0);

	RB_DrawArrays(polyMode);

	qglEnableClientState (GL_COLOR_ARRAY);
	for (i=0; i<numTMUs; i++)
		GL_EnableTexture(i);
	qglPolygonMode (GL_FRONT_AND_BACK, GL_FILL);

	if (r_showtris->value == 1)
		GL_Enable(GL_DEPTH_TEST);
}

/*
======================
RB_SetDefaultGLState

This should initialize all GL state that any part of the entire program
may touch, including the editor.
======================
*/
void RB_SetDefaultGLState( void ) {
	int		i;

	RB_LogComment( "--- R_SetDefaultGLState ---\n" );

	qglClearDepth( 1.0f );
	qglColor4f (1,1,1,1);

	// the vertex array is always enabled
	qglEnableClientState( GL_VERTEX_ARRAY );
	qglEnableClientState( GL_TEXTURE_COORD_ARRAY );
	qglDisableClientState( GL_COLOR_ARRAY );

	//
	// make sure our GL state vector is set correctly
	//
	memset( &backEnd.glState, 0, sizeof( backEnd.glState ) );
	backEnd.glState.forceGlState = true;

	qglColorMask( 1, 1, 1, 1 );

	qglEnable( GL_DEPTH_TEST );
	qglEnable( GL_BLEND );
	qglEnable( GL_SCISSOR_TEST );
	qglEnable( GL_CULL_FACE );
	qglDisable( GL_LIGHTING );
	qglDisable( GL_LINE_STIPPLE );
	qglDisable( GL_STENCIL_TEST );

	qglPolygonMode (GL_FRONT_AND_BACK, GL_FILL);
	qglDepthMask( GL_TRUE );
	qglDepthFunc( GL_ALWAYS );
 
	qglCullFace( GL_FRONT_AND_BACK );
	qglShadeModel( GL_SMOOTH );

	if ( r_useScissor.GetBool() ) {
		qglScissor( 0, 0, glConfig.vidWidth, glConfig.vidHeight );
	}

	for ( i = glConfig.maxTextureUnits - 1 ; i >= 0 ; i-- ) {
		GL_SelectTexture( i );

		// object linear texgen is our default
		qglTexGenf( GL_S, GL_TEXTURE_GEN_MODE, GL_OBJECT_LINEAR );
		qglTexGenf( GL_T, GL_TEXTURE_GEN_MODE, GL_OBJECT_LINEAR );
		qglTexGenf( GL_R, GL_TEXTURE_GEN_MODE, GL_OBJECT_LINEAR );
		qglTexGenf( GL_Q, GL_TEXTURE_GEN_MODE, GL_OBJECT_LINEAR );

		GL_TexEnv( GL_MODULATE );
		qglDisable( GL_TEXTURE_2D );
		if ( glConfig.texture3DAvailable ) {
			qglDisable( GL_TEXTURE_3D );
		}
		if ( glConfig.cubeMapAvailable ) {
			qglDisable( GL_TEXTURE_CUBE_MAP_EXT );
		}
	}
}

/*
==================
RB_NV20_DrawInteraction
==================
*/
static void	RB_NV20_DrawInteraction(const drawInteraction_t *din)
{
	const drawSurf_t *surf = din->surf;

	// load all the vertex program parameters
	qglProgramEnvParameter4fvARB(GL_VERTEX_PROGRAM_ARB, PP_LIGHT_ORIGIN, din->localLightOrigin.ToFloatPtr());
	qglProgramEnvParameter4fvARB(GL_VERTEX_PROGRAM_ARB, PP_VIEW_ORIGIN, din->localViewOrigin.ToFloatPtr());
	qglProgramEnvParameter4fvARB(GL_VERTEX_PROGRAM_ARB, PP_LIGHT_PROJECT_S, din->lightProjection[0].ToFloatPtr());
	qglProgramEnvParameter4fvARB(GL_VERTEX_PROGRAM_ARB, PP_LIGHT_PROJECT_T, din->lightProjection[1].ToFloatPtr());
	qglProgramEnvParameter4fvARB(GL_VERTEX_PROGRAM_ARB, PP_LIGHT_PROJECT_Q, din->lightProjection[2].ToFloatPtr());
	qglProgramEnvParameter4fvARB(GL_VERTEX_PROGRAM_ARB, PP_LIGHT_FALLOFF_S, din->lightProjection[3].ToFloatPtr());
	qglProgramEnvParameter4fvARB(GL_VERTEX_PROGRAM_ARB, PP_BUMP_MATRIX_S, din->bumpMatrix[0].ToFloatPtr());
	qglProgramEnvParameter4fvARB(GL_VERTEX_PROGRAM_ARB, PP_BUMP_MATRIX_T, din->bumpMatrix[1].ToFloatPtr());
	qglProgramEnvParameter4fvARB(GL_VERTEX_PROGRAM_ARB, PP_DIFFUSE_MATRIX_S, din->diffuseMatrix[0].ToFloatPtr());
	qglProgramEnvParameter4fvARB(GL_VERTEX_PROGRAM_ARB, PP_DIFFUSE_MATRIX_T, din->diffuseMatrix[1].ToFloatPtr());
	qglProgramEnvParameter4fvARB(GL_VERTEX_PROGRAM_ARB, PP_SPECULAR_MATRIX_S, din->specularMatrix[0].ToFloatPtr());
	qglProgramEnvParameter4fvARB(GL_VERTEX_PROGRAM_ARB, PP_SPECULAR_MATRIX_T, din->specularMatrix[1].ToFloatPtr());

	// set the constant colors
	qglCombinerParameterfvNV(GL_CONSTANT_COLOR0_NV, din->diffuseColor.ToFloatPtr());
	qglCombinerParameterfvNV(GL_CONSTANT_COLOR1_NV, din->specularColor.ToFloatPtr());

	// vertex color passes should be pretty rare (cross-faded bump map surfaces), so always
	// run them down as three-passes
	if (din->vertexColor != SVC_IGNORE) {
		qglEnableClientState(GL_COLOR_ARRAY);
		RB_NV20_DI_BumpAndLightPass(din, false);
		RB_NV20_DI_DiffuseColorPass(din);
		RB_NV20_DI_SpecularColorPass(din);
		qglDisableClientState(GL_COLOR_ARRAY);
		return;
	}

	qglColor3f(1, 1, 1);

	// on an ideal card, we would now just bind the textures and call a
	// single pass vertex / fragment program, but
	// on NV20, we need to decide which single / dual / tripple pass set of programs to use

	// ambient light could be done as a single pass if we want to optimize for it

	// monochrome light is two passes
	int		internalFormat = din->lightImage->internalFormat;

	if ((r_useNV20MonoLights.GetInteger() == 2) ||
	    (din->lightImage->isMonochrome && r_useNV20MonoLights.GetInteger())) {
		// do a two-pass rendering
		RB_NV20_DI_BumpAndLightPass(din, true);
		RB_NV20_DI_DiffuseAndSpecularColorPass(din);
	} else {
		// general case is three passes
		// ( bump dot lightDir ) * lightFalloff
		// diffuse * lightProject
		// specular * ( bump dot halfAngle extended ) * lightProject
		RB_NV20_DI_BumpAndLightPass(din, false);
		RB_NV20_DI_DiffuseColorPass(din);
		RB_NV20_DI_SpecularColorPass(din);
	}
}

/*
=====================
RB_StencilShadowPass

Stencil test should already be enabled, and the stencil buffer should have
been set to 128 on any surfaces that might receive shadows
=====================
*/
void RB_StencilShadowPass(const drawSurf_t *drawSurfs)
{
	if (!r_shadows.GetBool()) {
		return;
	}

	if (!drawSurfs) {
		return;
	}

	RB_LogComment("---------- RB_StencilShadowPass ----------\n");

	globalImages->BindNull();
	qglDisableClientState(GL_TEXTURE_COORD_ARRAY);

	// for visualizing the shadows
	if (r_showShadows.GetInteger()) {
		if (r_showShadows.GetInteger() == 2) {
			// draw filled in
			GL_State(GLS_DEPTHMASK | GLS_SRCBLEND_ONE | GLS_DSTBLEND_ONE | GLS_DEPTHFUNC_LESS);
		} else {
			// draw as lines, filling the depth buffer
			GL_State(GLS_SRCBLEND_ONE | GLS_DSTBLEND_ZERO | GLS_POLYMODE_LINE | GLS_DEPTHFUNC_ALWAYS);
		}
	} else {
		// don't write to the color buffer, just the stencil buffer
		GL_State(GLS_DEPTHMASK | GLS_COLORMASK | GLS_ALPHAMASK | GLS_DEPTHFUNC_LESS);
	}

	if (r_shadowPolygonFactor.GetFloat() || r_shadowPolygonOffset.GetFloat()) {
		qglPolygonOffset(r_shadowPolygonFactor.GetFloat(), -r_shadowPolygonOffset.GetFloat());
		qglEnable(GL_POLYGON_OFFSET_FILL);
	}

	qglStencilFunc(GL_ALWAYS, 1, 255);

	if (glConfig.depthBoundsTestAvailable && r_useDepthBoundsTest.GetBool()) {
		qglEnable(GL_DEPTH_BOUNDS_TEST_EXT);
	}

	RB_RenderDrawSurfChainWithFunction(drawSurfs, RB_T_Shadow);

	GL_Cull(CT_FRONT_SIDED);

	if (r_shadowPolygonFactor.GetFloat() || r_shadowPolygonOffset.GetFloat()) {
		qglDisable(GL_POLYGON_OFFSET_FILL);
	}

	if (glConfig.depthBoundsTestAvailable && r_useDepthBoundsTest.GetBool()) {
		qglDisable(GL_DEPTH_BOUNDS_TEST_EXT);
	}

	qglEnableClientState(GL_TEXTURE_COORD_ARRAY);

	qglStencilFunc(GL_GEQUAL, 128, 255);
	qglStencilOp(GL_KEEP, GL_KEEP, GL_KEEP);
}

/*
===================
RB_OutlinesPass

Draws outlines on surfaces with shader.hasOutlines set
===================
*/
static void RB_OutlinesPass( void ) {	

	int		outlines;
	float	outlinesAlpha;

	outlines		= r_outlines->value;
	outlinesAlpha	= r_outlinesAlpha->value;

	if ( !tess.shader->hasOutlines )
		return;	

	if ( !r_outlines->integer )
		return;

	GL_Bind( tr.whiteImage );
	qglColor4f( 0, 0, 0, outlinesAlpha );
		
	GL_State( GLS_POLYMODE_LINE | GLS_DEPTHMASK_TRUE | GLS_SRCBLEND_SRC_ALPHA | GLS_DSTBLEND_ONE_MINUS_SRC_ALPHA );
	qglPolygonMode( GL_BACK, GL_LINE );
	qglLineWidth( outlines + 1 );
			
	qglCullFace( GL_BACK );
		
	qglDisableClientState( GL_COLOR_ARRAY );
	qglDisableClientState( GL_TEXTURE_COORD_ARRAY );

	qglVertexPointer (3, GL_FLOAT, 16, tess.xyz);	// padded for SIMD
			
	if (qglLockArraysEXT) {
		qglLockArraysEXT(0, tess.numVertexes);
		GLimp_LogComment( "glLockArraysEXT\n" );
	}
	
	R_DrawElements( tess.numIndexes, tess.indexes );
		
	if (qglUnlockArraysEXT) {
		qglUnlockArraysEXT();
		GLimp_LogComment( "glUnlockArraysEXT\n" );
	}

	// FIX: Must reset these manually or renderer will b0rk!
	qglCullFace( GL_FRONT ); 
	qglLineWidth( 1 );
}

void CMistyFog2::Render(CWorldEffectsSystem *system)
{
	if (mFadeAlpha <= 0.0)
	{
		return;
	}

	qglMatrixMode(GL_PROJECTION);
	qglPushMatrix();
    qglLoadIdentity ();
	MYgluPerspective (80.0,  1.0,  4,  2048.0);

	qglMatrixMode(GL_MODELVIEW);
	qglPushMatrix();
    qglLoadIdentity ();
    qglRotatef (-90,  1, 0, 0);	    // put Z going up
    qglRotatef (90,  0, 0, 1);	    // put Z going up
    qglRotatef (0,  1, 0, 0);
    qglRotatef (-90,  0, 1, 0);
    qglRotatef (-90,  0, 0, 1);

	qglDisable(GL_TEXTURE_2D);
	GL_State(GLS_SRCBLEND_SRC_ALPHA|GLS_DSTBLEND_ONE);
	qglShadeModel (GL_SMOOTH);

	qglColorPointer(4, GL_FLOAT, 0, mColors);
	qglEnableClientState(GL_COLOR_ARRAY);

	qglVertexPointer( 3, GL_FLOAT, 0, mVerts );
	qglEnableClientState(GL_VERTEX_ARRAY);

	if (qglLockArraysEXT) 
	{
		qglLockArraysEXT(0, MISTYFOG_HEIGHT*MISTYFOG_WIDTH);
	}
	qglDrawElements(GL_QUADS, (MISTYFOG_HEIGHT-1)*(MISTYFOG_WIDTH-1)*4, GL_UNSIGNED_INT, mIndexes);
	if ( qglUnlockArraysEXT ) 
	{
		qglUnlockArraysEXT();
	}

	qglDisableClientState(GL_COLOR_ARRAY);
//	qglDisableClientState(GL_VERTEX_ARRAY);	 backend doesn't ever re=enable this properly

	qglPopMatrix();
	qglMatrixMode(GL_PROJECTION);
	qglPopMatrix();
	qglMatrixMode(GL_MODELVIEW);	// bug somewhere in the backend which requires this
}

static void DrawSkySideInner(struct image_s *image, const int mins[2], const int maxs[2])
{
	int s, t;

	GL_Bind(image);
	GLfloat vtx[3 * 1024];    // arbitrary sized
	GLfloat tex[2 * 1024];
	int     idx;

	GLboolean text  = qglIsEnabled(GL_TEXTURE_COORD_ARRAY);
	GLboolean glcol = qglIsEnabled(GL_COLOR_ARRAY);
	if (glcol)
	{
		qglDisableClientState(GL_COLOR_ARRAY);
	}
	if (!text)
	{
		qglEnableClientState(GL_TEXTURE_COORD_ARRAY);
	}

	//qglDisable (GL_BLEND);
	qglBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
	qglEnable(GL_BLEND);
	GL_TexEnv(GL_MODULATE);

	for (t = mins[1] + HALF_SKY_SUBDIVISIONS; t < maxs[1] + HALF_SKY_SUBDIVISIONS; t++)
	{
		idx = 0;

		for (s = mins[0] + HALF_SKY_SUBDIVISIONS; s <= maxs[0] + HALF_SKY_SUBDIVISIONS; s++)
		{
			memcpy(tex + idx * 2, s_skyTexCoords[t][s], sizeof(GLfloat) * 2);
			memcpy(vtx + idx * 3, s_skyPoints[t][s], sizeof(GLfloat) * 3);
			idx++;
			memcpy(tex + idx * 2, s_skyTexCoords[t + 1][s], sizeof(GLfloat) * 2);
			memcpy(vtx + idx * 3, s_skyPoints[t + 1][s], sizeof(GLfloat) * 3);
			idx++;
		}

		qglVertexPointer(3, GL_FLOAT, 0, vtx);
		qglTexCoordPointer(2, GL_FLOAT, 0, tex);
		qglDrawArrays(GL_TRIANGLE_STRIP, 0, idx);
	}

	qglDisable(GL_BLEND);
}