savagestate.c

Mesa is an open-source implementation of the OpenGL specification - a system for rendering interacti

	CLAMPED_FLOAT_TO_UBYTE(alphaRef,ctx->Color.AlphaRef);
         
        switch(ctx->Color.AlphaFunc)  { 
	case GL_NEVER: a = CF_Never; break;
	case GL_ALWAYS: a = CF_Always; break;
	case GL_LESS: a = CF_Less; break; 
	case GL_LEQUAL: a = CF_LessEqual; break;
	case GL_EQUAL: a = CF_Equal; break;
	case GL_GREATER: a = CF_Greater; break;
	case GL_GEQUAL: a = CF_GreaterEqual; break;
	case GL_NOTEQUAL: a = CF_NotEqual; break;
	default:return;
        }   

	imesa->regs.s3d.drawCtrl.ni.alphaTestEn = GL_TRUE;
	imesa->regs.s3d.drawCtrl.ni.alphaTestCmpFunc = a;
	imesa->regs.s3d.drawCtrl.ni.alphaRefVal = alphaRef;
    }
    else
    {
	imesa->regs.s3d.drawCtrl.ni.alphaTestEn = GL_FALSE;
    }

    /* Set/Reset Z-after-alpha*/

    imesa->regs.s3d.zBufCtrl.ni.wrZafterAlphaTst =
	imesa->regs.s3d.drawCtrl.ni.alphaTestEn;

    if (drawCtrl != imesa->regs.s3d.drawCtrl.ui ||
	zBufCtrl != imesa->regs.s3d.zBufCtrl.ui)
	imesa->dirty |= SAVAGE_UPLOAD_LOCAL;
}

static void savageDDBlendFuncSeparate_s4( GLcontext *ctx, GLenum sfactorRGB, 
					  GLenum dfactorRGB, GLenum sfactorA,
					  GLenum dfactorA )
{
    assert (dfactorRGB == dfactorA && sfactorRGB == sfactorA);
    savageBlendFunc_s4( ctx );
}
static void savageDDBlendFuncSeparate_s3d( GLcontext *ctx, GLenum sfactorRGB, 
					   GLenum dfactorRGB, GLenum sfactorA,
					   GLenum dfactorA )
{
    assert (dfactorRGB == dfactorA && sfactorRGB == sfactorA);
    savageBlendFunc_s3d( ctx );
}



static void savageDDDepthFunc_s4(GLcontext *ctx, GLenum func)
{
    savageContextPtr imesa = SAVAGE_CONTEXT(ctx);
    ZCmpFunc zmode;
    u_int32_t drawLocalCtrl = imesa->regs.s4.drawLocalCtrl.ui;
    u_int32_t zBufCtrl = imesa->regs.s4.zBufCtrl.ui;
    u_int32_t zWatermarks = imesa->regs.s4.zWatermarks.ui; /* FIXME: in DRM */

    /* set up z-buffer control register (global)
     * set up z-buffer offset register (global)
     * set up z read/write watermarks register (global)
     */

    switch(func)  { /* reversed (see savageCalcViewport) */
    case GL_NEVER: zmode = CF_Never; break;
    case GL_ALWAYS: zmode = CF_Always; break;
    case GL_LESS: zmode = CF_Greater; break; 
    case GL_LEQUAL: zmode = CF_GreaterEqual; break;
    case GL_EQUAL: zmode = CF_Equal; break;
    case GL_GREATER: zmode = CF_Less; break;
    case GL_GEQUAL: zmode = CF_LessEqual; break;
    case GL_NOTEQUAL: zmode = CF_NotEqual; break;
    default:return;
    } 
    if (ctx->Depth.Test)
    {

	imesa->regs.s4.zBufCtrl.ni.zCmpFunc = zmode;
	imesa->regs.s4.drawLocalCtrl.ni.zUpdateEn = ctx->Depth.Mask;
	imesa->regs.s4.drawLocalCtrl.ni.flushPdZbufWrites = GL_TRUE;
	imesa->regs.s4.zBufCtrl.ni.zBufEn = GL_TRUE;
    }
    else if (imesa->glCtx->Stencil.Enabled && imesa->hw_stencil)
    {
        /* Need to keep Z on for Stencil. */
	imesa->regs.s4.zBufCtrl.ni.zCmpFunc = CF_Always;
	imesa->regs.s4.zBufCtrl.ni.zBufEn   = GL_TRUE;
	imesa->regs.s4.drawLocalCtrl.ni.zUpdateEn = GL_FALSE;
	imesa->regs.s4.drawLocalCtrl.ni.flushPdZbufWrites = GL_FALSE;
    }
    else
    {

        if (imesa->regs.s4.drawLocalCtrl.ni.drawUpdateEn == GL_FALSE)
        {
            imesa->regs.s4.zBufCtrl.ni.zCmpFunc = CF_Always;
            imesa->regs.s4.zBufCtrl.ni.zBufEn   = GL_TRUE;
        }
        else

            /* DRAWUPDATE_REQUIRES_Z_ENABLED*/
        {
	    imesa->regs.s4.zBufCtrl.ni.zBufEn         = GL_FALSE;
        }
	imesa->regs.s4.drawLocalCtrl.ni.zUpdateEn = GL_FALSE;
	imesa->regs.s4.drawLocalCtrl.ni.flushPdZbufWrites = GL_FALSE;
    }

    if (drawLocalCtrl != imesa->regs.s4.drawLocalCtrl.ui)
	imesa->dirty |= SAVAGE_UPLOAD_LOCAL;
    if (zBufCtrl != imesa->regs.s4.zBufCtrl.ui ||
	zWatermarks != imesa->regs.s4.zWatermarks.ui)
	imesa->dirty |= SAVAGE_UPLOAD_GLOBAL;
}
static void savageDDDepthFunc_s3d(GLcontext *ctx, GLenum func)
{
    savageContextPtr imesa = SAVAGE_CONTEXT(ctx);
    ZCmpFunc zmode;
    u_int32_t drawCtrl = imesa->regs.s3d.drawCtrl.ui;
    u_int32_t zBufCtrl = imesa->regs.s3d.zBufCtrl.ui;
    u_int32_t zWatermarks = imesa->regs.s3d.zWatermarks.ui; /* FIXME: in DRM */

    /* set up z-buffer control register (global)
     * set up z-buffer offset register (global)
     * set up z read/write watermarks register (global)
     */
    switch(func)  { /* reversed (see savageCalcViewport) */
    case GL_NEVER: zmode = CF_Never; break;
    case GL_ALWAYS: zmode = CF_Always; break;
    case GL_LESS: zmode = CF_Greater; break; 
    case GL_LEQUAL: zmode = CF_GreaterEqual; break;
    case GL_EQUAL: zmode = CF_Equal; break;
    case GL_GREATER: zmode = CF_Less; break;
    case GL_GEQUAL: zmode = CF_LessEqual; break;
    case GL_NOTEQUAL: zmode = CF_NotEqual; break;
    default:return;
    } 
    if (ctx->Depth.Test)
    {
	imesa->regs.s3d.zBufCtrl.ni.zBufEn = GL_TRUE;
	imesa->regs.s3d.zBufCtrl.ni.zCmpFunc = zmode;
	imesa->regs.s3d.zBufCtrl.ni.zUpdateEn = ctx->Depth.Mask;
	
	imesa->regs.s3d.drawCtrl.ni.flushPdZbufWrites = GL_TRUE;
    }
    else
    {
	if (imesa->regs.s3d.zBufCtrl.ni.drawUpdateEn == GL_FALSE) {
	    imesa->regs.s3d.zBufCtrl.ni.zCmpFunc = CF_Always;
            imesa->regs.s3d.zBufCtrl.ni.zBufEn = GL_TRUE;
	}
        else

            /* DRAWUPDATE_REQUIRES_Z_ENABLED*/
        {
	    imesa->regs.s3d.zBufCtrl.ni.zBufEn = GL_FALSE;
        }
	imesa->regs.s3d.zBufCtrl.ni.zUpdateEn = GL_FALSE;
	imesa->regs.s3d.drawCtrl.ni.flushPdZbufWrites = GL_FALSE;
    }
  
    if (drawCtrl != imesa->regs.s3d.drawCtrl.ui ||
	zBufCtrl != imesa->regs.s3d.zBufCtrl.ui)
	imesa->dirty |= SAVAGE_UPLOAD_LOCAL;
    if (zWatermarks != imesa->regs.s3d.zWatermarks.ui)
	imesa->dirty |= SAVAGE_UPLOAD_GLOBAL;
}

static void savageDDDepthMask_s4(GLcontext *ctx, GLboolean flag)
{
    savageDDDepthFunc_s4(ctx,ctx->Depth.Func);
}
static void savageDDDepthMask_s3d(GLcontext *ctx, GLboolean flag)
{
    savageDDDepthFunc_s3d(ctx,ctx->Depth.Func);
}




/* =============================================================
 * Hardware clipping
 */


static void savageDDScissor( GLcontext *ctx, GLint x, GLint y, 
                             GLsizei w, GLsizei h )
{
    savageContextPtr imesa = SAVAGE_CONTEXT(ctx);

    /* Emit buffered commands with old scissor state. */
    FLUSH_BATCH(imesa);

    /* Mirror scissors in private context. */
    imesa->scissor.enabled = ctx->Scissor.Enabled;
    imesa->scissor.x = x;
    imesa->scissor.y = y;
    imesa->scissor.w = w;
    imesa->scissor.h = h;
}



static void savageDDDrawBuffer(GLcontext *ctx, GLenum mode )
{
    savageContextPtr imesa = SAVAGE_CONTEXT(ctx);
    u_int32_t destCtrl = imesa->regs.s4.destCtrl.ui;

    if (ctx->DrawBuffer->_NumColorDrawBuffers != 1) {
	FALLBACK( ctx, SAVAGE_FALLBACK_DRAW_BUFFER, GL_TRUE );
        return;
    }

    switch ( ctx->DrawBuffer->_ColorDrawBufferIndexes[0] ) {
    case BUFFER_FRONT_LEFT:
        imesa->IsDouble = GL_FALSE;
	imesa->regs.s4.destCtrl.ni.offset = imesa->savageScreen->frontOffset>>11;
	break;
    case BUFFER_BACK_LEFT:
        imesa->IsDouble = GL_TRUE;
	imesa->regs.s4.destCtrl.ni.offset = imesa->savageScreen->backOffset>>11;
	break;
    default:
	FALLBACK( ctx, SAVAGE_FALLBACK_DRAW_BUFFER, GL_TRUE );
	return;
    }
    
    imesa->NotFirstFrame = GL_FALSE;
    savageXMesaSetClipRects(imesa);
    FALLBACK(ctx, SAVAGE_FALLBACK_DRAW_BUFFER, GL_FALSE);

    if (destCtrl != imesa->regs.s4.destCtrl.ui)
        imesa->dirty |= SAVAGE_UPLOAD_GLOBAL;
}

static void savageDDReadBuffer(GLcontext *ctx, GLenum mode )
{
   /* nothing, until we implement h/w glRead/CopyPixels or CopyTexImage */
}

#if 0
static void savageDDSetColor(GLcontext *ctx, 
                             GLubyte r, GLubyte g,
                             GLubyte b, GLubyte a )
{
    savageContextPtr imesa = SAVAGE_CONTEXT(ctx);
    imesa->MonoColor = savagePackColor( imesa->savageScreen->frontFormat, r, g, b, a );
}
#endif

/* =============================================================
 * Window position and viewport transformation
 */

void savageCalcViewport( GLcontext *ctx )
{
   savageContextPtr imesa = SAVAGE_CONTEXT(ctx);
   const GLfloat *v = ctx->Viewport._WindowMap.m;
   GLfloat *m = imesa->hw_viewport;

   m[MAT_SX] =   v[MAT_SX];
   m[MAT_TX] =   v[MAT_TX] + imesa->drawX + SUBPIXEL_X;
   m[MAT_SY] = - v[MAT_SY];
   m[MAT_TY] = - v[MAT_TY] + imesa->driDrawable->h + imesa->drawY + SUBPIXEL_Y;
   /* Depth range is reversed (far: 0, near: 1) so that float depth
    * compensates for loss of accuracy of far coordinates. */
   if (imesa->float_depth && imesa->savageScreen->zpp == 2) {
       /* The Savage 16-bit floating point depth format can't encode
	* numbers < 2^-16. Make sure all depth values stay greater
	* than that. */
       m[MAT_SZ] = - v[MAT_SZ] * imesa->depth_scale * (65535.0/65536.0);
       m[MAT_TZ] = 1.0 - v[MAT_TZ] * imesa->depth_scale * (65535.0/65536.0);
   } else {
       m[MAT_SZ] = - v[MAT_SZ] * imesa->depth_scale;
       m[MAT_TZ] = 1.0 - v[MAT_TZ] * imesa->depth_scale;
   }

   imesa->SetupNewInputs = ~0;
}

static void savageViewport( GLcontext *ctx, 
			    GLint x, GLint y, 
			    GLsizei width, GLsizei height )
{
   savageCalcViewport( ctx );
}

static void savageDepthRange( GLcontext *ctx, 
			      GLclampd nearval, GLclampd farval )
{
   savageCalcViewport( ctx );
}


/* =============================================================
 * Miscellaneous
 */

static void savageDDClearColor(GLcontext *ctx, 
			       const GLfloat color[4] )
{
    savageContextPtr imesa = SAVAGE_CONTEXT(ctx);
    GLubyte c[4];
    CLAMPED_FLOAT_TO_UBYTE(c[0], color[0]);
    CLAMPED_FLOAT_TO_UBYTE(c[1], color[1]);
    CLAMPED_FLOAT_TO_UBYTE(c[2], color[2]);
    CLAMPED_FLOAT_TO_UBYTE(c[3], color[3]);

    imesa->ClearColor = savagePackColor( imesa->savageScreen->frontFormat,
					 c[0], c[1], c[2], c[3] );
}

/* Fallback to swrast for select and feedback.
 */
static void savageRenderMode( GLcontext *ctx, GLenum mode )
{
   FALLBACK( ctx, SAVAGE_FALLBACK_RENDERMODE, (mode != GL_RENDER) );
}


#if HW_CULL

/* =============================================================
 * Culling - the savage isn't quite as clean here as the rest of
 *           its interfaces, but it's not bad.
 */
static void savageDDCullFaceFrontFace(GLcontext *ctx, GLenum unused)
{
    savageContextPtr imesa = SAVAGE_CONTEXT(ctx);
    GLuint cullMode=imesa->LcsCullMode;        
    switch (ctx->Polygon.CullFaceMode)
    {
        case GL_FRONT:
            switch (ctx->Polygon.FrontFace)
            {
                case GL_CW:
                    cullMode = BCM_CW;
                    break;
                case GL_CCW:
                    cullMode = BCM_CCW;
                    break;
            }
            break;

        case GL_BACK:
            switch (ctx->Polygon.FrontFace)
            {
                case GL_CW:
                    cullMode = BCM_CCW;
                    break;
                case GL_CCW:
                    cullMode = BCM_CW;
                    break;
            }
            break;
    }
    imesa->LcsCullMode = cullMode;    
    imesa->new_state |= SAVAGE_NEW_CULL;
}
#endif /* end #if HW_CULL */

static void savageUpdateCull( GLcontext *ctx )
{
#if HW_CULL
    savageContextPtr imesa = SAVAGE_CONTEXT(ctx);
    GLuint cullMode;
    if (ctx->Polygon.CullFlag &&
	imesa->raster_primitive >= GL_TRIANGLES &&
	ctx->Polygon.CullFaceMode != GL_FRONT_AND_BACK)
	cullMode = imesa->LcsCullMode;
    else
	cullMode = BCM_None;
    if (imesa->savageScreen->chipset >= S3_SAVAGE4) {
	if (imesa->regs.s4.drawCtrl1.ni.cullMode != cullMode) {
	    imesa->regs.s4.drawCtrl1.ni.cullMode = cullMode;
	    imesa->dirty |= SAVAGE_UPLOAD_GLOBAL;
	}
    } else {
	if (imesa->regs.s3d.drawCtrl.ni.cullMode != cullMode) {
	    imesa->regs.s3d.drawCtrl.ni.cullMode = cullMode;
	    imesa->dirty |= SAVAGE_UPLOAD_LOCAL;
	}
    }
#endif /* end  #if HW_CULL */
}



/* =============================================================
 * Color masks
 */

/* Savage4 can disable draw updates when all channels are
 * masked. Savage3D has a bit called drawUpdateEn, but it doesn't seem
 * to have any effect. If only some channels are masked we need a
 * software fallback on all chips.
 */
static void savageDDColorMask_s4(GLcontext *ctx, 
				 GLboolean r, GLboolean g, 
				 GLboolean b, GLboolean a )
{
    savageContextPtr imesa = SAVAGE_CONTEXT( ctx );
    GLboolean passAny, passAll;

    if (ctx->Visual.alphaBits) {
	passAny = b || g || r || a;
	passAll = r && g && b && a;
    } else {
	passAny = b || g || r;
	passAll = r && g && b;
    }

    if (passAny) {
	if (!imesa->regs.s4.drawLocalCtrl.ni.drawUpdateEn) {
	    imesa->regs.s4.drawLocalCtrl.ni.drawUpdateEn = GL_TRUE;
	    imesa->dirty |= SAVAGE_UPLOAD_LOCAL;
	}
	FALLBACK (ctx, SAVAGE_FALLBACK_COLORMASK, !passAll);
    } else if (imesa->regs.s4.drawLocalCtrl.ni.drawUpdateEn) {
	imesa->regs.s4.drawLocalCtrl.ni.drawUpdateEn = GL_FALSE;
	imesa->dirty |= SAVAGE_UPLOAD_LOCAL;
    }
}
static void savageDDColorMask_s3d(GLcontext *ctx, 
				  GLboolean r, GLboolean g, 
				  GLboolean b, GLboolean a )
{
    if (ctx->Visual.alphaBits)
	FALLBACK (ctx, SAVAGE_FALLBACK_COLORMASK, !(r && g && b && a));
    else
	FALLBACK (ctx, SAVAGE_FALLBACK_COLORMASK, !(r && g && b));
}