[Mesa-dev] [PATCH 10/22] swrast: rewrite stencil test code
Brian Paul
brianp at vmware.com
Sun Dec 18 19:08:15 PST 2011
Stop using the deprecated renderbuffer Get/Put Row/Values functions.
Consolidate code paths, etc. The file is nearly half the size it used
to be!
---
src/mesa/swrast/s_stencil.c | 1119 ++++++++++---------------------------------
1 files changed, 260 insertions(+), 859 deletions(-)
diff --git a/src/mesa/swrast/s_stencil.c b/src/mesa/swrast/s_stencil.c
index 5abf817..41aff9b 100644
--- a/src/mesa/swrast/s_stencil.c
+++ b/src/mesa/swrast/s_stencil.c
@@ -65,194 +65,170 @@ get_stencil_address(struct gl_renderbuffer *rb, GLint x, GLint y)
}
+/**
+ * Compute/return the offset of the stencil value in a pixel.
+ * For example, if the format is Z24+S8, the position of the stencil bits
+ * within the 4-byte pixel will be either 0 or 3.
+ */
+static GLint
+get_stencil_offset(gl_format format)
+{
+ const GLubyte one = 1;
+ GLubyte pixel[MAX_PIXEL_BYTES];
+ GLint bpp = _mesa_get_format_bytes(format);
+ GLint i;
+
+ assert(_mesa_get_format_bits(format, GL_STENCIL_BITS) == 8);
+ memset(pixel, 0, sizeof(pixel));
+ _mesa_pack_ubyte_stencil_row(format, 1, &one, pixel);
+
+ for (i = 0; i < bpp; i++) {
+ if (pixel[i])
+ return i;
+ }
+
+ _mesa_problem(NULL, "get_stencil_offset() failed\n");
+ return 0;
+}
+
+
+/** Clamp the stencil value to [0, 255] */
+static inline GLubyte
+clamp(GLint val)
+{
+ if (val < 0)
+ return 0;
+ else if (val > 255)
+ return 255;
+ else
+ return val;
+}
+
+
+#define STENCIL_OP(NEW_VAL) \
+ if (invmask == 0) { \
+ for (i = j = 0; i < n; i++, j += stride) { \
+ if (mask[i]) { \
+ GLubyte s = stencil[j]; \
+ (void) s; \
+ stencil[j] = (GLubyte) (NEW_VAL); \
+ } \
+ } \
+ } \
+ else { \
+ for (i = j = 0; i < n; i++, j += stride) { \
+ if (mask[i]) { \
+ GLubyte s = stencil[j]; \
+ stencil[j] = (GLubyte) ((invmask & s) | (wrtmask & (NEW_VAL))); \
+ } \
+ } \
+ }
+
/**
* Apply the given stencil operator to the array of stencil values.
* Don't touch stencil[i] if mask[i] is zero.
- * Input: n - size of stencil array
- * oper - the stencil buffer operator
- * face - 0 or 1 for front or back face operation
- * stencil - array of stencil values
- * mask - array [n] of flag: 1=apply operator, 0=don't apply operator
- * Output: stencil - modified values
+ * @param n number of stencil values
+ * @param oper the stencil buffer operator
+ * @param face 0 or 1 for front or back face operation
+ * @param stencil array of stencil values (in/out)
+ * @param mask array [n] of flag: 1=apply operator, 0=don't apply operator
+ * @param stride stride between stencil values
*/
static void
-apply_stencil_op( const struct gl_context *ctx, GLenum oper, GLuint face,
- GLuint n, GLubyte stencil[], const GLubyte mask[] )
+apply_stencil_op(const struct gl_context *ctx, GLenum oper, GLuint face,
+ GLuint n, GLubyte stencil[], const GLubyte mask[],
+ GLint stride)
{
const GLubyte ref = ctx->Stencil.Ref[face];
const GLubyte wrtmask = ctx->Stencil.WriteMask[face];
const GLubyte invmask = (GLubyte) (~wrtmask);
- const GLubyte stencilMax = (1 << ctx->DrawBuffer->Visual.stencilBits) - 1;
- GLuint i;
+ GLuint i, j;
switch (oper) {
- case GL_KEEP:
- /* do nothing */
- break;
- case GL_ZERO:
- if (invmask==0) {
- for (i=0;i<n;i++) {
- if (mask[i]) {
- stencil[i] = 0;
- }
- }
- }
- else {
- for (i=0;i<n;i++) {
- if (mask[i]) {
- stencil[i] = (GLubyte) (stencil[i] & invmask);
- }
- }
- }
- break;
- case GL_REPLACE:
- if (invmask==0) {
- for (i=0;i<n;i++) {
- if (mask[i]) {
- stencil[i] = ref;
- }
- }
- }
- else {
- for (i=0;i<n;i++) {
- if (mask[i]) {
- GLubyte s = stencil[i];
- stencil[i] = (GLubyte) ((invmask & s ) | (wrtmask & ref));
- }
- }
- }
- break;
- case GL_INCR:
- if (invmask==0) {
- for (i=0;i<n;i++) {
- if (mask[i]) {
- GLubyte s = stencil[i];
- if (s < stencilMax) {
- stencil[i] = (GLubyte) (s+1);
- }
- }
- }
- }
- else {
- for (i=0;i<n;i++) {
- if (mask[i]) {
- /* VERIFY logic of adding 1 to a write-masked value */
- GLubyte s = stencil[i];
- if (s < stencilMax) {
- stencil[i] = (GLubyte) ((invmask & s) | (wrtmask & (s+1)));
- }
- }
- }
- }
- break;
- case GL_DECR:
- if (invmask==0) {
- for (i=0;i<n;i++) {
- if (mask[i]) {
- GLubyte s = stencil[i];
- if (s>0) {
- stencil[i] = (GLubyte) (s-1);
- }
- }
- }
- }
- else {
- for (i=0;i<n;i++) {
- if (mask[i]) {
- /* VERIFY logic of subtracting 1 to a write-masked value */
- GLubyte s = stencil[i];
- if (s>0) {
- stencil[i] = (GLubyte) ((invmask & s) | (wrtmask & (s-1)));
- }
- }
- }
- }
- break;
- case GL_INCR_WRAP_EXT:
- if (invmask==0) {
- for (i=0;i<n;i++) {
- if (mask[i]) {
- stencil[i]++;
- }
- }
- }
- else {
- for (i=0;i<n;i++) {
- if (mask[i]) {
- GLubyte s = stencil[i];
- stencil[i] = (GLubyte) ((invmask & s) | (wrtmask & (s+1)));
- }
- }
- }
- break;
- case GL_DECR_WRAP_EXT:
- if (invmask==0) {
- for (i=0;i<n;i++) {
- if (mask[i]) {
- stencil[i]--;
- }
- }
- }
- else {
- for (i=0;i<n;i++) {
- if (mask[i]) {
- GLubyte s = stencil[i];
- stencil[i] = (GLubyte) ((invmask & s) | (wrtmask & (s-1)));
- }
- }
- }
- break;
- case GL_INVERT:
- if (invmask==0) {
- for (i=0;i<n;i++) {
- if (mask[i]) {
- GLubyte s = stencil[i];
- stencil[i] = (GLubyte) ~s;
- }
- }
- }
- else {
- for (i=0;i<n;i++) {
- if (mask[i]) {
- GLubyte s = stencil[i];
- stencil[i] = (GLubyte) ((invmask & s) | (wrtmask & ~s));
- }
- }
- }
- break;
- default:
- _mesa_problem(ctx, "Bad stencil op in apply_stencil_op");
+ case GL_KEEP:
+ /* do nothing */
+ break;
+ case GL_ZERO:
+ /* replace stencil buf values with zero */
+ STENCIL_OP(0);
+ break;
+ case GL_REPLACE:
+ /* replace stencil buf values with ref value */
+ STENCIL_OP(ref);
+ break;
+ case GL_INCR:
+ /* increment stencil buf values, with clamping */
+ STENCIL_OP(clamp(s + 1));
+ break;
+ case GL_DECR:
+ /* increment stencil buf values, with clamping */
+ STENCIL_OP(clamp(s - 1));
+ break;
+ case GL_INCR_WRAP_EXT:
+ /* increment stencil buf values, without clamping */
+ STENCIL_OP(s + 1);
+ break;
+ case GL_DECR_WRAP_EXT:
+ /* increment stencil buf values, without clamping */
+ STENCIL_OP(s - 1);
+ break;
+ case GL_INVERT:
+ /* replace stencil buf values with inverted value */
+ STENCIL_OP(~s);
+ break;
+ default:
+ _mesa_problem(ctx, "Bad stencil op in apply_stencil_op");
}
}
+#define STENCIL_TEST(FUNC) \
+ for (i = j = 0; i < n; i++, j += stride) { \
+ if (mask[i]) { \
+ s = (GLubyte) (stencil[j] & valueMask); \
+ if (FUNC) { \
+ /* stencil pass */ \
+ fail[i] = 0; \
+ } \
+ else { \
+ /* stencil fail */ \
+ fail[i] = 1; \
+ mask[i] = 0; \
+ } \
+ } \
+ else { \
+ fail[i] = 0; \
+ } \
+ }
+
+
/**
* Apply stencil test to an array of stencil values (before depth buffering).
- * Input: face - 0 or 1 for front or back-face polygons
- * n - number of pixels in the array
- * stencil - array of [n] stencil values
- * mask - array [n] of flag: 0=skip the pixel, 1=stencil the pixel
- * Output: mask - pixels which fail the stencil test will have their
- * mask flag set to 0.
- * stencil - updated stencil values (where the test passed)
- * Return: GL_FALSE = all pixels failed, GL_TRUE = zero or more pixels passed.
+ * For the values that fail, we'll apply the GL_STENCIL_FAIL operator to
+ * the stencil values.
+ *
+ * @param face 0 or 1 for front or back-face polygons
+ * @param n number of pixels in the array
+ * @param stencil array of [n] stencil values (in/out)
+ * @param mask array [n] of flag: 0=skip the pixel, 1=stencil the pixel,
+ * values are set to zero where the stencil test fails.
+ * @param stride stride between stencil values
+ * @return GL_FALSE = all pixels failed, GL_TRUE = zero or more pixels passed.
*/
static GLboolean
-do_stencil_test( struct gl_context *ctx, GLuint face, GLuint n, GLubyte stencil[],
- GLubyte mask[] )
+do_stencil_test(struct gl_context *ctx, GLuint face, GLuint n,
+ GLubyte stencil[], GLubyte mask[], GLint stride)
{
GLubyte fail[MAX_WIDTH];
GLboolean allfail = GL_FALSE;
- GLuint i;
+ GLuint i, j;
const GLuint valueMask = ctx->Stencil.ValueMask[face];
- const GLubyte r = (GLubyte) (ctx->Stencil.Ref[face] & valueMask);
+ const GLubyte ref = (GLubyte) (ctx->Stencil.Ref[face] & valueMask);
GLubyte s;
- ASSERT(n <= MAX_WIDTH);
-
/*
* Perform stencil test. The results of this operation are stored
* in the fail[] array:
@@ -263,140 +239,39 @@ do_stencil_test( struct gl_context *ctx, GLuint face, GLuint n, GLubyte stencil[
* ENDIF
*/
switch (ctx->Stencil.Function[face]) {
- case GL_NEVER:
- /* never pass; always fail */
- for (i=0;i<n;i++) {
- if (mask[i]) {
- mask[i] = 0;
- fail[i] = 1;
- }
- else {
- fail[i] = 0;
- }
- }
- allfail = GL_TRUE;
- break;
- case GL_LESS:
- for (i=0;i<n;i++) {
- if (mask[i]) {
- s = (GLubyte) (stencil[i] & valueMask);
- if (r < s) {
- /* passed */
- fail[i] = 0;
- }
- else {
- fail[i] = 1;
- mask[i] = 0;
- }
- }
- else {
- fail[i] = 0;
- }
- }
- break;
- case GL_LEQUAL:
- for (i=0;i<n;i++) {
- if (mask[i]) {
- s = (GLubyte) (stencil[i] & valueMask);
- if (r <= s) {
- /* pass */
- fail[i] = 0;
- }
- else {
- fail[i] = 1;
- mask[i] = 0;
- }
- }
- else {
- fail[i] = 0;
- }
- }
- break;
- case GL_GREATER:
- for (i=0;i<n;i++) {
- if (mask[i]) {
- s = (GLubyte) (stencil[i] & valueMask);
- if (r > s) {
- /* passed */
- fail[i] = 0;
- }
- else {
- fail[i] = 1;
- mask[i] = 0;
- }
- }
- else {
- fail[i] = 0;
- }
- }
- break;
- case GL_GEQUAL:
- for (i=0;i<n;i++) {
- if (mask[i]) {
- s = (GLubyte) (stencil[i] & valueMask);
- if (r >= s) {
- /* passed */
- fail[i] = 0;
- }
- else {
- fail[i] = 1;
- mask[i] = 0;
- }
- }
- else {
- fail[i] = 0;
- }
- }
- break;
- case GL_EQUAL:
- for (i=0;i<n;i++) {
- if (mask[i]) {
- s = (GLubyte) (stencil[i] & valueMask);
- if (r == s) {
- /* passed */
- fail[i] = 0;
- }
- else {
- fail[i] = 1;
- mask[i] = 0;
- }
- }
- else {
- fail[i] = 0;
- }
- }
- break;
- case GL_NOTEQUAL:
- for (i=0;i<n;i++) {
- if (mask[i]) {
- s = (GLubyte) (stencil[i] & valueMask);
- if (r != s) {
- /* passed */
- fail[i] = 0;
- }
- else {
- fail[i] = 1;
- mask[i] = 0;
- }
- }
- else {
- fail[i] = 0;
- }
- }
- break;
- case GL_ALWAYS:
- /* always pass */
- for (i=0;i<n;i++) {
- fail[i] = 0;
- }
- break;
- default:
- _mesa_problem(ctx, "Bad stencil func in gl_stencil_span");
- return 0;
+ case GL_NEVER:
+ STENCIL_TEST(0);
+ allfail = GL_TRUE;
+ break;
+ case GL_LESS:
+ STENCIL_TEST(ref < s);
+ break;
+ case GL_LEQUAL:
+ STENCIL_TEST(ref <= s);
+ break;
+ case GL_GREATER:
+ STENCIL_TEST(ref > s);
+ break;
+ case GL_GEQUAL:
+ STENCIL_TEST(ref >= s);
+ break;
+ case GL_EQUAL:
+ STENCIL_TEST(ref == s);
+ break;
+ case GL_NOTEQUAL:
+ STENCIL_TEST(ref != s);
+ break;
+ case GL_ALWAYS:
+ STENCIL_TEST(1);
+ break;
+ default:
+ _mesa_problem(ctx, "Bad stencil func in gl_stencil_span");
+ return 0;
}
if (ctx->Stencil.FailFunc[face] != GL_KEEP) {
- apply_stencil_op( ctx, ctx->Stencil.FailFunc[face], face, n, stencil, fail );
+ apply_stencil_op(ctx, ctx->Stencil.FailFunc[face], face, n, stencil,
+ fail, stride);
}
return !allfail;
@@ -422,54 +297,100 @@ compute_pass_fail_masks(GLuint n, const GLubyte origMask[],
/**
- * Apply stencil and depth testing to the span of pixels.
- * Both software and hardware stencil buffers are acceptable.
- * Input: n - number of pixels in the span
- * x, y - location of leftmost pixel in span
- * z - array [n] of z values
- * mask - array [n] of flags (1=test this pixel, 0=skip the pixel)
- * Output: mask - array [n] of flags (1=stencil and depth test passed)
- * Return: GL_FALSE - all fragments failed the testing
- * GL_TRUE - one or more fragments passed the testing
- *
+ * Get 8-bit stencil values from random locations in the stencil buffer.
*/
-static GLboolean
-stencil_and_ztest_span(struct gl_context *ctx, SWspan *span, GLuint face)
+static void
+get_s8_values(struct gl_context *ctx, struct gl_renderbuffer *rb,
+ GLuint count, const GLint x[], const GLint y[],
+ GLubyte stencil[])
+{
+ const GLint w = rb->Width, h = rb->Height;
+ const GLubyte *map = (const GLubyte *) rb->Data;
+ GLuint i;
+
+ if (rb->Format == MESA_FORMAT_S8) {
+ const GLuint rowStride = rb->RowStride;
+ for (i = 0; i < count; i++) {
+ if (x[i] >= 0 && y[i] >= 0 && x[i] < w && y[i] < h) {
+ stencil[i] = *(map + y[i] * rowStride + x[i]);
+ }
+ }
+ }
+ else {
+ const GLuint bpp = _mesa_get_format_bytes(rb->Format);
+ const GLuint rowStride = rb->RowStride * bpp;
+ for (i = 0; i < count; i++) {
+ if (x[i] >= 0 && y[i] >= 0 && x[i] < w && y[i] < h) {
+ const GLubyte *src = map + y[i] * rowStride + x[i] * bpp;
+ _mesa_unpack_ubyte_stencil_row(rb->Format, 1, src, &stencil[i]);
+ }
+ }
+ }
+}
+
+
+/**
+ * Put 8-bit stencil values at random locations into the stencil buffer.
+ */
+static void
+put_s8_values(struct gl_context *ctx, struct gl_renderbuffer *rb,
+ GLuint count, const GLint x[], const GLint y[],
+ const GLubyte stencil[])
+{
+ const GLint w = rb->Width, h = rb->Height;
+ GLuint i;
+
+ for (i = 0; i < count; i++) {
+ if (x[i] >= 0 && y[i] >= 0 && x[i] < w && y[i] < h) {
+ GLubyte *dst = get_stencil_address(rb, x[i], y[i]);
+ _mesa_pack_ubyte_stencil_row(rb->Format, 1, &stencil[i], dst);
+ }
+ }
+}
+
+
+/**
+ * /return GL_TRUE = one or more fragments passed,
+ * GL_FALSE = all fragments failed.
+ */
+GLboolean
+_swrast_stencil_and_ztest_span(struct gl_context *ctx, SWspan *span)
{
struct gl_framebuffer *fb = ctx->DrawBuffer;
- struct gl_renderbuffer *rb = fb->_StencilBuffer;
- GLubyte stencilRow[MAX_WIDTH];
- GLubyte *stencil;
- const GLuint n = span->end;
- const GLint x = span->x;
- const GLint y = span->y;
+ struct gl_renderbuffer *rb = fb->Attachment[BUFFER_STENCIL].Renderbuffer;
+ const GLint stencilOffset = get_stencil_offset(rb->Format);
+ const GLint stencilStride = _mesa_get_format_bytes(rb->Format);
+ const GLuint face = (span->facing == 0) ? 0 : ctx->Stencil._BackFace;
+ const GLuint count = span->end;
GLubyte *mask = span->array->mask;
+ GLubyte stencilTemp[MAX_WIDTH];
+ GLubyte *stencilBuf;
- ASSERT((span->arrayMask & SPAN_XY) == 0);
- ASSERT(ctx->Stencil.Enabled);
- ASSERT(n <= MAX_WIDTH);
-#ifdef DEBUG
- if (ctx->Depth.Test) {
- ASSERT(span->arrayMask & SPAN_Z);
+ if (span->arrayMask & SPAN_XY) {
+ /* read stencil values from random locations */
+ get_s8_values(ctx, rb, count, span->array->x, span->array->y,
+ stencilTemp);
+ stencilBuf = stencilTemp;
}
-#endif
-
- stencil = (GLubyte *) rb->GetPointer(ctx, rb, x, y);
- if (!stencil) {
- rb->GetRow(ctx, rb, n, x, y, stencilRow);
- stencil = stencilRow;
+ else {
+ /* Processing a horizontal run of pixels. Since stencil is always
+ * 8 bits for all MESA_FORMATs, we just need to use the right offset
+ * and stride to access them.
+ */
+ stencilBuf = get_stencil_address(rb, span->x, span->y) + stencilOffset;
}
/*
* Apply the stencil test to the fragments.
* failMask[i] is 1 if the stencil test failed.
*/
- if (do_stencil_test( ctx, face, n, stencil, mask ) == GL_FALSE) {
+ if (!do_stencil_test(ctx, face, count, stencilBuf, mask, stencilStride)) {
/* all fragments failed the stencil test, we're done. */
span->writeAll = GL_FALSE;
- if (!rb->GetPointer(ctx, rb, 0, 0)) {
- /* put updated stencil values into buffer */
- rb->PutRow(ctx, rb, n, x, y, stencil, NULL);
+ if (span->arrayMask & SPAN_XY) {
+ /* need to write the updated stencil values back to the buffer */
+ put_s8_values(ctx, rb, count, span->array->x, span->array->y,
+ stencilTemp);
}
return GL_FALSE;
}
@@ -479,11 +400,12 @@ stencil_and_ztest_span(struct gl_context *ctx, SWspan *span, GLuint face)
* and apply Zpass and Zfail stencil ops.
*/
if (ctx->Depth.Test == GL_FALSE ||
- ctx->DrawBuffer->_DepthBuffer == NULL) {
+ ctx->DrawBuffer->Attachment[BUFFER_DEPTH].Renderbuffer == NULL) {
/*
* No depth buffer, just apply zpass stencil function to active pixels.
*/
- apply_stencil_op( ctx, ctx->Stencil.ZPassFunc[face], face, n, stencil, mask );
+ apply_stencil_op(ctx, ctx->Stencil.ZPassFunc[face], face, count,
+ stencilBuf, mask, stencilStride);
}
else {
/*
@@ -492,29 +414,28 @@ stencil_and_ztest_span(struct gl_context *ctx, SWspan *span, GLuint face)
GLubyte passMask[MAX_WIDTH], failMask[MAX_WIDTH], origMask[MAX_WIDTH];
/* save the current mask bits */
- memcpy(origMask, mask, n * sizeof(GLubyte));
+ memcpy(origMask, mask, count * sizeof(GLubyte));
/* apply the depth test */
_swrast_depth_test_span(ctx, span);
- compute_pass_fail_masks(n, origMask, mask, passMask, failMask);
+ compute_pass_fail_masks(count, origMask, mask, passMask, failMask);
/* apply the pass and fail operations */
if (ctx->Stencil.ZFailFunc[face] != GL_KEEP) {
- apply_stencil_op( ctx, ctx->Stencil.ZFailFunc[face], face,
- n, stencil, failMask );
+ apply_stencil_op(ctx, ctx->Stencil.ZFailFunc[face], face,
+ count, stencilBuf, failMask, stencilStride);
}
if (ctx->Stencil.ZPassFunc[face] != GL_KEEP) {
- apply_stencil_op( ctx, ctx->Stencil.ZPassFunc[face], face,
- n, stencil, passMask );
+ apply_stencil_op(ctx, ctx->Stencil.ZPassFunc[face], face,
+ count, stencilBuf, passMask, stencilStride);
}
}
- /*
- * Write updated stencil values back into hardware stencil buffer.
- */
- if (!rb->GetPointer(ctx, rb, 0, 0)) {
- rb->PutRow(ctx, rb, n, x, y, stencil, NULL);
+ /* Write updated stencil values back into hardware stencil buffer */
+ if (span->arrayMask & SPAN_XY) {
+ put_s8_values(ctx, rb, count, span->array->x, span->array->y,
+ stencilBuf);
}
span->writeAll = GL_FALSE;
@@ -524,526 +445,6 @@ stencil_and_ztest_span(struct gl_context *ctx, SWspan *span, GLuint face)
-/*
- * Return the address of a stencil buffer value given the window coords:
- */
-#define STENCIL_ADDRESS(X, Y) (stencilStart + (Y) * stride + (X))
-
-
-
-/**
- * Apply the given stencil operator for each pixel in the array whose
- * mask flag is set.
- * \note This is for software stencil buffers only.
- * Input: n - number of pixels in the span
- * x, y - array of [n] pixels
- * operator - the stencil buffer operator
- * mask - array [n] of flag: 1=apply operator, 0=don't apply operator
- */
-static void
-apply_stencil_op_to_pixels( struct gl_context *ctx,
- GLuint n, const GLint x[], const GLint y[],
- GLenum oper, GLuint face, const GLubyte mask[] )
-{
- struct gl_framebuffer *fb = ctx->DrawBuffer;
- struct gl_renderbuffer *rb = fb->_StencilBuffer;
- const GLubyte stencilMax = (1 << fb->Visual.stencilBits) - 1;
- const GLubyte ref = ctx->Stencil.Ref[face];
- const GLubyte wrtmask = ctx->Stencil.WriteMask[face];
- const GLubyte invmask = (GLubyte) (~wrtmask);
- GLuint i;
- GLubyte *stencilStart = (GLubyte *) rb->Data;
- const GLuint stride = rb->Width;
-
- ASSERT(rb->GetPointer(ctx, rb, 0, 0));
-
- switch (oper) {
- case GL_KEEP:
- /* do nothing */
- break;
- case GL_ZERO:
- if (invmask==0) {
- for (i=0;i<n;i++) {
- if (mask[i]) {
- GLubyte *sptr = STENCIL_ADDRESS( x[i], y[i] );
- *sptr = 0;
- }
- }
- }
- else {
- for (i=0;i<n;i++) {
- if (mask[i]) {
- GLubyte *sptr = STENCIL_ADDRESS( x[i], y[i] );
- *sptr = (GLubyte) (invmask & *sptr);
- }
- }
- }
- break;
- case GL_REPLACE:
- if (invmask==0) {
- for (i=0;i<n;i++) {
- if (mask[i]) {
- GLubyte *sptr = STENCIL_ADDRESS( x[i], y[i] );
- *sptr = ref;
- }
- }
- }
- else {
- for (i=0;i<n;i++) {
- if (mask[i]) {
- GLubyte *sptr = STENCIL_ADDRESS( x[i], y[i] );
- *sptr = (GLubyte) ((invmask & *sptr ) | (wrtmask & ref));
- }
- }
- }
- break;
- case GL_INCR:
- if (invmask==0) {
- for (i=0;i<n;i++) {
- if (mask[i]) {
- GLubyte *sptr = STENCIL_ADDRESS( x[i], y[i] );
- if (*sptr < stencilMax) {
- *sptr = (GLubyte) (*sptr + 1);
- }
- }
- }
- }
- else {
- for (i=0;i<n;i++) {
- if (mask[i]) {
- GLubyte *sptr = STENCIL_ADDRESS( x[i], y[i] );
- if (*sptr < stencilMax) {
- *sptr = (GLubyte) ((invmask & *sptr) | (wrtmask & (*sptr+1)));
- }
- }
- }
- }
- break;
- case GL_DECR:
- if (invmask==0) {
- for (i=0;i<n;i++) {
- if (mask[i]) {
- GLubyte *sptr = STENCIL_ADDRESS( x[i], y[i] );
- if (*sptr>0) {
- *sptr = (GLubyte) (*sptr - 1);
- }
- }
- }
- }
- else {
- for (i=0;i<n;i++) {
- if (mask[i]) {
- GLubyte *sptr = STENCIL_ADDRESS( x[i], y[i] );
- if (*sptr>0) {
- *sptr = (GLubyte) ((invmask & *sptr) | (wrtmask & (*sptr-1)));
- }
- }
- }
- }
- break;
- case GL_INCR_WRAP_EXT:
- if (invmask==0) {
- for (i=0;i<n;i++) {
- if (mask[i]) {
- GLubyte *sptr = STENCIL_ADDRESS( x[i], y[i] );
- *sptr = (GLubyte) (*sptr + 1);
- }
- }
- }
- else {
- for (i=0;i<n;i++) {
- if (mask[i]) {
- GLubyte *sptr = STENCIL_ADDRESS( x[i], y[i] );
- *sptr = (GLubyte) ((invmask & *sptr) | (wrtmask & (*sptr+1)));
- }
- }
- }
- break;
- case GL_DECR_WRAP_EXT:
- if (invmask==0) {
- for (i=0;i<n;i++) {
- if (mask[i]) {
- GLubyte *sptr = STENCIL_ADDRESS( x[i], y[i] );
- *sptr = (GLubyte) (*sptr - 1);
- }
- }
- }
- else {
- for (i=0;i<n;i++) {
- if (mask[i]) {
- GLubyte *sptr = STENCIL_ADDRESS( x[i], y[i] );
- *sptr = (GLubyte) ((invmask & *sptr) | (wrtmask & (*sptr-1)));
- }
- }
- }
- break;
- case GL_INVERT:
- if (invmask==0) {
- for (i=0;i<n;i++) {
- if (mask[i]) {
- GLubyte *sptr = STENCIL_ADDRESS( x[i], y[i] );
- *sptr = (GLubyte) (~*sptr);
- }
- }
- }
- else {
- for (i=0;i<n;i++) {
- if (mask[i]) {
- GLubyte *sptr = STENCIL_ADDRESS( x[i], y[i] );
- *sptr = (GLubyte) ((invmask & *sptr) | (wrtmask & ~*sptr));
- }
- }
- }
- break;
- default:
- _mesa_problem(ctx, "Bad stencilop in apply_stencil_op_to_pixels");
- }
-}
-
-
-
-/**
- * Apply stencil test to an array of pixels before depth buffering.
- *
- * \note Used for software stencil buffer only.
- * Input: n - number of pixels in the span
- * x, y - array of [n] pixels to stencil
- * mask - array [n] of flag: 0=skip the pixel, 1=stencil the pixel
- * Output: mask - pixels which fail the stencil test will have their
- * mask flag set to 0.
- * \return GL_FALSE = all pixels failed, GL_TRUE = zero or more pixels passed.
- */
-static GLboolean
-stencil_test_pixels( struct gl_context *ctx, GLuint face, GLuint n,
- const GLint x[], const GLint y[], GLubyte mask[] )
-{
- const struct gl_framebuffer *fb = ctx->DrawBuffer;
- struct gl_renderbuffer *rb = fb->_StencilBuffer;
- GLubyte fail[MAX_WIDTH];
- GLubyte r, s;
- GLuint i;
- GLboolean allfail = GL_FALSE;
- const GLuint valueMask = ctx->Stencil.ValueMask[face];
- const GLubyte *stencilStart = (GLubyte *) rb->Data;
- const GLuint stride = rb->Width;
-
- ASSERT(rb->GetPointer(ctx, rb, 0, 0));
-
- /*
- * Perform stencil test. The results of this operation are stored
- * in the fail[] array:
- * IF fail[i] is non-zero THEN
- * the stencil fail operator is to be applied
- * ELSE
- * the stencil fail operator is not to be applied
- * ENDIF
- */
-
- switch (ctx->Stencil.Function[face]) {
- case GL_NEVER:
- /* always fail */
- for (i=0;i<n;i++) {
- if (mask[i]) {
- mask[i] = 0;
- fail[i] = 1;
- }
- else {
- fail[i] = 0;
- }
- }
- allfail = GL_TRUE;
- break;
- case GL_LESS:
- r = (GLubyte) (ctx->Stencil.Ref[face] & valueMask);
- for (i=0;i<n;i++) {
- if (mask[i]) {
- const GLubyte *sptr = STENCIL_ADDRESS(x[i],y[i]);
- s = (GLubyte) (*sptr & valueMask);
- if (r < s) {
- /* passed */
- fail[i] = 0;
- }
- else {
- fail[i] = 1;
- mask[i] = 0;
- }
- }
- else {
- fail[i] = 0;
- }
- }
- break;
- case GL_LEQUAL:
- r = (GLubyte) (ctx->Stencil.Ref[face] & valueMask);
- for (i=0;i<n;i++) {
- if (mask[i]) {
- const GLubyte *sptr = STENCIL_ADDRESS(x[i],y[i]);
- s = (GLubyte) (*sptr & valueMask);
- if (r <= s) {
- /* pass */
- fail[i] = 0;
- }
- else {
- fail[i] = 1;
- mask[i] = 0;
- }
- }
- else {
- fail[i] = 0;
- }
- }
- break;
- case GL_GREATER:
- r = (GLubyte) (ctx->Stencil.Ref[face] & valueMask);
- for (i=0;i<n;i++) {
- if (mask[i]) {
- const GLubyte *sptr = STENCIL_ADDRESS(x[i],y[i]);
- s = (GLubyte) (*sptr & valueMask);
- if (r > s) {
- /* passed */
- fail[i] = 0;
- }
- else {
- fail[i] = 1;
- mask[i] = 0;
- }
- }
- else {
- fail[i] = 0;
- }
- }
- break;
- case GL_GEQUAL:
- r = (GLubyte) (ctx->Stencil.Ref[face] & valueMask);
- for (i=0;i<n;i++) {
- if (mask[i]) {
- const GLubyte *sptr = STENCIL_ADDRESS(x[i],y[i]);
- s = (GLubyte) (*sptr & valueMask);
- if (r >= s) {
- /* passed */
- fail[i] = 0;
- }
- else {
- fail[i] = 1;
- mask[i] = 0;
- }
- }
- else {
- fail[i] = 0;
- }
- }
- break;
- case GL_EQUAL:
- r = (GLubyte) (ctx->Stencil.Ref[face] & valueMask);
- for (i=0;i<n;i++) {
- if (mask[i]) {
- const GLubyte *sptr = STENCIL_ADDRESS(x[i],y[i]);
- s = (GLubyte) (*sptr & valueMask);
- if (r == s) {
- /* passed */
- fail[i] = 0;
- }
- else {
- fail[i] = 1;
- mask[i] = 0;
- }
- }
- else {
- fail[i] = 0;
- }
- }
- break;
- case GL_NOTEQUAL:
- r = (GLubyte) (ctx->Stencil.Ref[face] & valueMask);
- for (i=0;i<n;i++) {
- if (mask[i]) {
- const GLubyte *sptr = STENCIL_ADDRESS(x[i],y[i]);
- s = (GLubyte) (*sptr & valueMask);
- if (r != s) {
- /* passed */
- fail[i] = 0;
- }
- else {
- fail[i] = 1;
- mask[i] = 0;
- }
- }
- else {
- fail[i] = 0;
- }
- }
- break;
- case GL_ALWAYS:
- /* always pass */
- for (i=0;i<n;i++) {
- fail[i] = 0;
- }
- break;
- default:
- _mesa_problem(ctx, "Bad stencil func in gl_stencil_pixels");
- return 0;
- }
-
- if (ctx->Stencil.FailFunc[face] != GL_KEEP) {
- apply_stencil_op_to_pixels( ctx, n, x, y, ctx->Stencil.FailFunc[face],
- face, fail );
- }
-
- return !allfail;
-}
-
-
-
-static void
-get_s8_values(struct gl_context *ctx, struct gl_renderbuffer *rb,
- GLuint count, const GLint x[], const GLint y[],
- GLubyte stencil[])
-{
- const GLint w = rb->Width, h = rb->Height;
- const GLubyte *map = (const GLubyte *) rb->Data;
- GLuint i;
-
- if (rb->Format == MESA_FORMAT_S8) {
- const GLuint rowStride = rb->RowStride;
- for (i = 0; i < count; i++) {
- if (x[i] >= 0 && y[i] >= 0 && x[i] < w && y[i] < h) {
- stencil[i] = *(map + y[i] * rowStride + x[i]);
- }
- }
- }
- else {
- const GLuint bpp = _mesa_get_format_bytes(rb->Format);
- const GLuint rowStride = rb->RowStride * bpp;
- for (i = 0; i < count; i++) {
- if (x[i] >= 0 && y[i] >= 0 && x[i] < w && y[i] < h) {
- const GLubyte *src = map + y[i] * rowStride + x[i] * bpp;
- _mesa_unpack_ubyte_stencil_row(rb->Format, 1, src, &stencil[i]);
- }
- }
- }
-}
-
-
-/**
- * Apply stencil and depth testing to an array of pixels.
- * This is used both for software and hardware stencil buffers.
- *
- * The comments in this function are a bit sparse but the code is
- * almost identical to stencil_and_ztest_span(), which is well
- * commented.
- *
- * Input: n - number of pixels in the array
- * x, y - array of [n] pixel positions
- * z - array [n] of z values
- * mask - array [n] of flags (1=test this pixel, 0=skip the pixel)
- * Output: mask - array [n] of flags (1=stencil and depth test passed)
- * Return: GL_FALSE - all fragments failed the testing
- * GL_TRUE - one or more fragments passed the testing
- */
-static GLboolean
-stencil_and_ztest_pixels( struct gl_context *ctx, SWspan *span, GLuint face )
-{
- GLubyte passMask[MAX_WIDTH], failMask[MAX_WIDTH], origMask[MAX_WIDTH];
- struct gl_framebuffer *fb = ctx->DrawBuffer;
- struct gl_renderbuffer *rb = fb->_StencilBuffer;
- const GLuint n = span->end;
- const GLint *x = span->array->x;
- const GLint *y = span->array->y;
- GLubyte *mask = span->array->mask;
-
- ASSERT(span->arrayMask & SPAN_XY);
- ASSERT(ctx->Stencil.Enabled);
- ASSERT(n <= MAX_WIDTH);
-
- if (!rb->GetPointer(ctx, rb, 0, 0)) {
- /* No direct access */
- GLubyte stencil[MAX_WIDTH];
-
- ASSERT(rb->DataType == GL_UNSIGNED_BYTE);
- get_s8_values(ctx, rb, n, x, y, stencil);
-
- memcpy(origMask, mask, n * sizeof(GLubyte));
-
- (void) do_stencil_test(ctx, face, n, stencil, mask);
-
- if (ctx->Depth.Test == GL_FALSE) {
- apply_stencil_op(ctx, ctx->Stencil.ZPassFunc[face], face,
- n, stencil, mask);
- }
- else {
- GLubyte tmpMask[MAX_WIDTH];
- memcpy(tmpMask, mask, n * sizeof(GLubyte));
-
- _swrast_depth_test_span(ctx, span);
-
- compute_pass_fail_masks(n, tmpMask, mask, passMask, failMask);
-
- if (ctx->Stencil.ZFailFunc[face] != GL_KEEP) {
- apply_stencil_op(ctx, ctx->Stencil.ZFailFunc[face], face,
- n, stencil, failMask);
- }
- if (ctx->Stencil.ZPassFunc[face] != GL_KEEP) {
- apply_stencil_op(ctx, ctx->Stencil.ZPassFunc[face], face,
- n, stencil, passMask);
- }
- }
-
- /* Write updated stencil values into hardware stencil buffer */
- rb->PutValues(ctx, rb, n, x, y, stencil, origMask);
-
- return GL_TRUE;
- }
- else {
- /* Direct access to stencil buffer */
-
- if (stencil_test_pixels(ctx, face, n, x, y, mask) == GL_FALSE) {
- /* all fragments failed the stencil test, we're done. */
- return GL_FALSE;
- }
-
- if (ctx->Depth.Test==GL_FALSE) {
- apply_stencil_op_to_pixels(ctx, n, x, y,
- ctx->Stencil.ZPassFunc[face], face, mask);
- }
- else {
- memcpy(origMask, mask, n * sizeof(GLubyte));
-
- _swrast_depth_test_span(ctx, span);
-
- compute_pass_fail_masks(n, origMask, mask, passMask, failMask);
-
- if (ctx->Stencil.ZFailFunc[face] != GL_KEEP) {
- apply_stencil_op_to_pixels(ctx, n, x, y,
- ctx->Stencil.ZFailFunc[face],
- face, failMask);
- }
- if (ctx->Stencil.ZPassFunc[face] != GL_KEEP) {
- apply_stencil_op_to_pixels(ctx, n, x, y,
- ctx->Stencil.ZPassFunc[face],
- face, passMask);
- }
- }
-
- return GL_TRUE; /* one or more fragments passed both tests */
- }
-}
-
-
-/**
- * /return GL_TRUE = one or more fragments passed,
- * GL_FALSE = all fragments failed.
- */
-GLboolean
-_swrast_stencil_and_ztest_span(struct gl_context *ctx, SWspan *span)
-{
- const GLuint face = (span->facing == 0) ? 0 : ctx->Stencil._BackFace;
-
- if (span->arrayMask & SPAN_XY)
- return stencil_and_ztest_pixels(ctx, span, face);
- else
- return stencil_and_ztest_span(ctx, span, face);
-}
-
/**
* Return a span of stencil values from the stencil buffer.
--
1.7.3.4
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