diff options
| -rw-r--r-- | src/mesa/main/stencil.c | 183 |
1 files changed, 104 insertions, 79 deletions
diff --git a/src/mesa/main/stencil.c b/src/mesa/main/stencil.c index df316267f6..efb5ff688b 100644 --- a/src/mesa/main/stencil.c +++ b/src/mesa/main/stencil.c @@ -1,4 +1,4 @@ -/* $Id: stencil.c,v 1.10 1999/11/24 18:48:31 brianp Exp $ */ +/* $Id: stencil.c,v 1.11 1999/12/04 21:23:55 brianp Exp $ */ /* * Mesa 3-D graphics library @@ -38,14 +38,6 @@ #endif -#if STENCIL_BITS==8 -# define STENCIL_MAX 0xff -#elif STENCIL_BITS==16 -# define STENCIL_MAX 0xffff -#else - illegal number of stencil bits -#endif - void @@ -172,25 +164,21 @@ _mesa_StencilOp( GLenum fail, GLenum zfail, GLenum zpass ) /* Stencil Logic: IF stencil test fails THEN + Apply fail-op to stencil value Don't write the pixel (RGBA,Z) - Execute FailOp -ELSE - Write the pixel -ENDIF - -Perform Depth Test - -IF depth test passes OR no depth buffer THEN - Execute ZPass - Write the pixel ELSE - Execute ZFail + IF doing depth test && depth test fails THEN + Apply zfail-op to stencil value + Write RGBA and Z to appropriate buffers + ELSE + Apply zpass-op to stencil value ENDIF */ + /* * Return the address of a stencil buffer value given the window coords: */ @@ -200,21 +188,19 @@ ENDIF /* - * Apply the given stencil operator for each pixel in the span whose - * mask flag is set. + * Apply the given stencil operator to the array of stencil values. + * Don't touch stencil[i] if mask[i] is zero. * Input: n - number of pixels in the span - * x, y - location of leftmost pixel in the span * oper - the stencil buffer operator + * stencil - array of stencil values * mask - array [n] of flag: 1=apply operator, 0=don't apply operator */ -static void apply_stencil_op_to_span( GLcontext *ctx, - GLuint n, GLint x, GLint y, - GLenum oper, GLubyte mask[] ) +static void apply_stencil_op( GLcontext *ctx, GLenum oper, + GLuint n, GLstencil stencil[], GLubyte mask[] ) { const GLstencil ref = ctx->Stencil.Ref; const GLstencil wrtmask = ctx->Stencil.WriteMask; const GLstencil invmask = (GLstencil) (~ctx->Stencil.WriteMask); - GLstencil *stencil = STENCIL_ADDRESS( x, y ); GLuint i; switch (oper) { @@ -353,7 +339,7 @@ static void apply_stencil_op_to_span( GLcontext *ctx, } break; default: - gl_problem(ctx, "Bad stencilop in apply_stencil_op_to_span"); + gl_problem(ctx, "Bad stencil op in apply_stencil_op"); } } @@ -528,7 +514,9 @@ GLint gl_stencil_span( GLcontext *ctx, return 0; } - apply_stencil_op_to_span( ctx, n, x, y, ctx->Stencil.FailFunc, fail ); + if (ctx->Stencil.FailFunc != GL_KEEP) { + apply_stencil_op( ctx, ctx->Stencil.FailFunc, n, stencil, fail ); + } return (allfail) ? 0 : 1; } @@ -548,11 +536,13 @@ void gl_depth_stencil_span( GLcontext *ctx, GLuint n, GLint x, GLint y, const GLdepth z[], GLubyte mask[] ) { + GLstencil *stencil = STENCIL_ADDRESS(x, y); + if (ctx->Depth.Test==GL_FALSE) { /* * No depth buffer, just apply zpass stencil function to active pixels. */ - apply_stencil_op_to_span( ctx, n, x, y, ctx->Stencil.ZPassFunc, mask ); + apply_stencil_op( ctx, ctx->Stencil.ZPassFunc, n, stencil, mask ); } else { /* @@ -561,31 +551,36 @@ void gl_depth_stencil_span( GLcontext *ctx, GLubyte passmask[MAX_WIDTH], failmask[MAX_WIDTH], oldmask[MAX_WIDTH]; GLuint i; - /* init pass and fail masks to zero, copy mask[] to oldmask[] */ - for (i=0;i<n;i++) { - passmask[i] = failmask[i] = 0; - oldmask[i] = mask[i]; - } + /* save the current mask bits */ + MEMCPY(oldmask, mask, n * sizeof(GLubyte)); /* apply the depth test */ if (ctx->Driver.DepthTestSpan) (*ctx->Driver.DepthTestSpan)( ctx, n, x, y, z, mask ); - /* set the stencil pass/fail flags according to result of depth test */ + /* Set the stencil pass/fail flags according to result of depth testing. + * if oldmask[i] == 0 then + * Don't touch the stencil value + * else if oldmask[i] and newmask[i] then + * Depth test passed + * else + * assert(oldmask[i] && !newmask[i]) + * Depth test failed + * endif + */ for (i=0;i<n;i++) { - if (oldmask[i]) { - if (mask[i]) { - passmask[i] = 1; - } - else { - failmask[i] = 1; - } - } + ASSERT(mask[i] == 0 || mask[i] == 1); + passmask[i] = oldmask[i] & mask[i]; + failmask[i] = oldmask[i] & (mask[i] ^ 1); } /* apply the pass and fail operations */ - apply_stencil_op_to_span( ctx, n, x, y, ctx->Stencil.ZFailFunc, failmask ); - apply_stencil_op_to_span( ctx, n, x, y, ctx->Stencil.ZPassFunc, passmask ); + if (ctx->Stencil.ZFailFunc != GL_KEEP) { + apply_stencil_op( ctx, ctx->Stencil.ZFailFunc, n, stencil, failmask ); + } + if (ctx->Stencil.ZPassFunc != GL_KEEP) { + apply_stencil_op( ctx, ctx->Stencil.ZPassFunc, n, stencil, passmask ); + } } } @@ -965,26 +960,27 @@ void gl_depth_stencil_pixels( GLcontext *ctx, GLubyte passmask[PB_SIZE], failmask[PB_SIZE], oldmask[PB_SIZE]; GLuint i; - /* init pass and fail masks to zero */ - for (i=0;i<n;i++) { - passmask[i] = failmask[i] = 0; - oldmask[i] = mask[i]; - } + /* save the current mask bits */ + MEMCPY(oldmask, mask, n * sizeof(GLubyte)); /* apply the depth test */ if (ctx->Driver.DepthTestPixels) (*ctx->Driver.DepthTestPixels)( ctx, n, x, y, z, mask ); - /* set the stencil pass/fail flags according to result of depth test */ + /* Set the stencil pass/fail flags according to result of depth testing. + * if oldmask[i] == 0 then + * Don't touch the stencil value + * else if oldmask[i] and newmask[i] then + * Depth test passed + * else + * assert(oldmask[i] && !newmask[i]) + * Depth test failed + * endif + */ for (i=0;i<n;i++) { - if (oldmask[i]) { - if (mask[i]) { - passmask[i] = 1; - } - else { - failmask[i] = 1; - } - } + ASSERT(mask[i] == 0 || mask[i] == 1); + passmask[i] = oldmask[i] & mask[i]; + failmask[i] = oldmask[i] & (mask[i] ^ 1); } /* apply the pass and fail operations */ @@ -1071,10 +1067,6 @@ void gl_alloc_stencil_buffer( GLcontext *ctx ) -/* - * Clear the stencil buffer. If the stencil buffer doesn't exist yet we'll - * allocate it now. - */ void gl_clear_stencil_buffer( GLcontext *ctx ) { if (ctx->Visual->StencilBits==0 || !ctx->DrawBuffer->Stencil) { @@ -1084,30 +1076,63 @@ void gl_clear_stencil_buffer( GLcontext *ctx ) if (ctx->Scissor.Enabled) { /* clear scissor region only */ - GLint y; - GLint width = ctx->DrawBuffer->Xmax - ctx->DrawBuffer->Xmin + 1; - for (y=ctx->DrawBuffer->Ymin; y<=ctx->DrawBuffer->Ymax; y++) { - GLstencil *ptr = STENCIL_ADDRESS( ctx->DrawBuffer->Xmin, y ); + const GLint width = ctx->DrawBuffer->Xmax - ctx->DrawBuffer->Xmin + 1; + if (ctx->Stencil.WriteMask != STENCIL_MAX) { + /* must apply mask to the clear */ + GLint y; + for (y=ctx->DrawBuffer->Ymin; y<=ctx->DrawBuffer->Ymax; y++) { + GLstencil *ptr = STENCIL_ADDRESS( ctx->DrawBuffer->Xmin, y ); + GLint x; + const GLstencil mask = ctx->Stencil.WriteMask; + const GLstencil invMask = ~mask; + const GLstencil clearVal = (ctx->Stencil.Clear & mask); + for (x = 0; x < width; x++) { + ptr[x] = (ptr[x] & invMask) | clearVal; + } + } + } + else { + /* no masking */ + GLint y; + for (y=ctx->DrawBuffer->Ymin; y<=ctx->DrawBuffer->Ymax; y++) { + GLstencil *ptr = STENCIL_ADDRESS( ctx->DrawBuffer->Xmin, y ); #if STENCIL_BITS==8 - MEMSET( ptr, ctx->Stencil.Clear, width * sizeof(GLstencil) ); + MEMSET( ptr, ctx->Stencil.Clear, width * sizeof(GLstencil) ); #else - GLint x; - for (x = 0; x < width; x++) - ptr[x] = ctx->Stencil.Clear; + GLint x; + for (x = 0; x < width; x++) + ptr[x] = ctx->Stencil.Clear; #endif + } } } else { /* clear whole stencil buffer */ + if (ctx->Stencil.WriteMask != STENCIL_MAX) { + /* must apply mask to the clear */ + const GLuint n = ctx->DrawBuffer->Width * ctx->DrawBuffer->Height; + GLstencil *buffer = ctx->DrawBuffer->Stencil; + const GLstencil mask = ctx->Stencil.WriteMask; + const GLstencil invMask = ~mask; + const GLstencil clearVal = (ctx->Stencil.Clear & mask); + GLuint i; + for (i = 0; i < n; i++) { + buffer[i] = (buffer[i] & invMask) | clearVal; + } + } + else { + /* clear whole buffer without masking */ + const GLuint n = ctx->DrawBuffer->Width * ctx->DrawBuffer->Height; + GLstencil *buffer = ctx->DrawBuffer->Stencil; + #if STENCIL_BITS==8 - MEMSET( ctx->DrawBuffer->Stencil, ctx->Stencil.Clear, - ctx->DrawBuffer->Width * ctx->DrawBuffer->Height * sizeof(GLstencil) ); + MEMSET(buffer, ctx->Stencil.Clear, n * sizeof(GLstencil) ); #else - GLuint i; - GLuint pixels = ctx->DrawBuffer->Width * ctx->DrawBuffer->Height; - GLstencil *buffer = ctx->DrawBuffer->Stencil; - for (i = 0; i < pixels; i++) - ptr[i] = ctx->Stencil.Clear; + GLuint i; + for (i = 0; i < n; i++) { + buffer[i] = ctx->Stencil.Clear; + } #endif + } } } |