/*
* Mesa 3-D graphics library
* Version: 7.1
*
* Copyright (C) 1999-2007 Brian Paul All Rights Reserved.
*
* Permission is hereby granted, free of charge, to any person obtaining a
* copy of this software and associated documentation files (the "Software"),
* to deal in the Software without restriction, including without limitation
* the rights to use, copy, modify, merge, publish, distribute, sublicense,
* and/or sell copies of the Software, and to permit persons to whom the
* Software is furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included
* in all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
* OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
* BRIAN PAUL BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
* AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
* CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*/
/**
* \file stencil.c
* Stencil operations.
*
* Note: There's some conflict between GL_EXT_stencil_two_side and
* OpenGL 2.0's two-sided stencil feature.
*
* With GL_EXT_stencil_two_side, calling glStencilOp/Func/Mask() only the
* front OR back face state (as set by glActiveStencilFaceEXT) is set.
*
* But with OpenGL 2.0, calling glStencilOp/Func/Mask() sets BOTH the
* front AND back state.
*
* Also, note that GL_ATI_separate_stencil is different as well:
* glStencilFuncSeparateATI(GLenum frontfunc, GLenum backfunc, ...) vs.
* glStencilFuncSeparate(GLenum face, GLenum func, ...).
*
* This problem is solved by keeping three sets of stencil state:
* state[0] = GL_FRONT state.
* state[1] = OpenGL 2.0 / GL_ATI_separate_stencil GL_BACK state.
* state[2] = GL_EXT_stencil_two_side GL_BACK state.
*/
#include "glheader.h"
#include "imports.h"
#include "context.h"
#include "macros.h"
#include "stencil.h"
#include "mtypes.h"
static GLboolean
validate_stencil_op(struct gl_context *ctx, GLenum op)
{
switch (op) {
case GL_KEEP:
case GL_ZERO:
case GL_REPLACE:
case GL_INCR:
case GL_DECR:
case GL_INVERT:
return GL_TRUE;
case GL_INCR_WRAP_EXT:
case GL_DECR_WRAP_EXT:
if (ctx->Extensions.EXT_stencil_wrap) {
return GL_TRUE;
}
/* FALL-THROUGH */
default:
return GL_FALSE;
}
}
static GLboolean
validate_stencil_func(struct gl_context *ctx, GLenum func)
{
switch (func) {
case GL_NEVER:
case GL_LESS:
case GL_LEQUAL:
case GL_GREATER:
case GL_GEQUAL:
case GL_EQUAL:
case GL_NOTEQUAL:
case GL_ALWAYS:
return GL_TRUE;
default:
return GL_FALSE;
}
}
/**
* Set the clear value for the stencil buffer.
*
* \param s clear value.
*
* \sa glClearStencil().
*
* Updates gl_stencil_attrib::Clear. On change
* flushes the vertices and notifies the driver via
* the dd_function_table::ClearStencil callback.
*/
void GLAPIENTRY
_mesa_ClearStencil( GLint s )
{
GET_CURRENT_CONTEXT(ctx);
ASSERT_OUTSIDE_BEGIN_END(ctx);
if (ctx->Stencil.Clear == (GLuint) s)
return;
FLUSH_VERTICES(ctx, _NEW_STENCIL);
ctx->Stencil.Clear = (GLuint) s;
if (ctx->Driver.ClearStencil) {
ctx->Driver.ClearStencil( ctx, s );
}
}
/**
* Set the function and reference value for stencil testing.
*
* \param frontfunc front test function.
* \param backfunc back test function.
* \param ref front and back reference value.
* \param mask front and back bitmask.
*
* \sa glStencilFunc().
*
* Verifies the parameters and updates the respective values in
* __struct gl_contextRec::Stencil. On change flushes the vertices and notifies the
* driver via the dd_function_table::StencilFunc callback.
*/
void GLAPIENTRY
_mesa_StencilFuncSeparateATI( GLenum frontfunc, GLenum backfunc, GLint ref, GLuint mask )
{
GET_CURRENT_CONTEXT(ctx);
const GLint stencilMax = (1 << ctx->DrawBuffer->Visual.stencilBits) - 1;
ASSERT_OUTSIDE_BEGIN_END(ctx);
if (!validate_stencil_func(ctx, frontfunc)) {
_mesa_error(ctx, GL_INVALID_ENUM,
"glStencilFuncSeparateATI(frontfunc)");
return;
}
if (!validate_stencil_func(ctx, backfunc)) {
_mesa_error(ctx, GL_INVALID_ENUM,
"glStencilFuncSeparateATI(backfunc)");
return;
}
ref = CLAMP( ref, 0, stencilMax );
/* set both front and back state */
if (ctx->Stencil.Function[0] == frontfunc &&
ctx->Stencil.Function[1] == backfunc &&
ctx->Stencil.ValueMask[0] == mask &&
ctx->Stencil.ValueMask[1] == mask &&
ctx->Stencil.Ref[0] == ref &&
ctx->Stencil.Ref[1] == ref)
return;
FLUSH_VERTICES(ctx, _NEW_STENCIL);
ctx->Stencil.Function[0] = frontfunc;
ctx->Stencil.Function[1] = backfunc;
ctx->Stencil.Ref[0] = ctx->Stencil.Ref[1] = ref;
ctx->Stencil.ValueMask[0] = ctx->Stencil.ValueMask[1] = mask;
if (ctx->Driver.StencilFuncSeparate) {
ctx->Driver.StencilFuncSeparate(ctx, GL_FRONT,
frontfunc, ref, mask);
ctx->Driver.StencilFuncSeparate(ctx, GL_BACK,
backfunc, ref, mask);
}
}
/**
* Set the function and reference value for stencil testing.
*
* \param func test function.
* \param ref reference value.
* \param mask bitmask.
*
* \sa glStencilFunc().
*
* Verifies the parameters and updates the respective values in
* __struct gl_contextRec::Stencil. On change flushes the vertices and notifies the
* driver via the dd_function_table::StencilFunc callback.
*/
void GLAPIENTRY
_mesa_StencilFunc( GLenum func, GLint ref, GLuint mask )
{
GET_CURRENT_CONTEXT(ctx);
const GLint stencilMax = (1 << ctx->DrawBuffer->Visual.stencilBits) - 1;
const GLint face = ctx->Stencil.ActiveFace;
ASSERT_OUTSIDE_BEGIN_END(ctx);
if (!validate_stencil_func(ctx, func)) {
_mesa_error(ctx, GL_INVALID_ENUM, "glStencilFunc(func)");
return;
}
ref = CLAMP( ref, 0, stencilMax );
if (face != 0) {
if (ctx->Stencil.Function[face] == func &&
ctx->Stencil.ValueMask[face] == mask &&
ctx->Stencil.Ref[face] == ref)
return;
FLUSH_VERTICES(ctx, _NEW_STENCIL);
ctx->Stencil.Function[face] = func;
ctx->Stencil.Ref[face] = ref;
ctx->Stencil.ValueMask[face] = mask;
/* Only propagate the change to the driver if EXT_stencil_two_side
* is enabled.
*/
if (ctx->Driver.StencilFuncSeparate && ctx->Stencil.TestTwoSide) {
ctx->Driver.StencilFuncSeparate(ctx, GL_BACK, func, ref, mask);
}
}
else {
/* set both front and back state */
if (ctx->Stencil.Function[0] == func &&
ctx->Stencil.Function[1] == func &&
ctx->Stencil.ValueMask[0] == mask &&
ctx->Stencil.ValueMask[1] == mask &&
ctx->Stencil.Ref[0] == ref &&
ctx->Stencil.Ref[1] == ref)
return;
FLUSH_VERTICES(ctx, _NEW_STENCIL);
ctx->Stencil.Function[0] = ctx->Stencil.Function[1] = func;
ctx->Stencil.Ref[0] = ctx->Stencil.Ref[1] = ref;
ctx->Stencil.ValueMask[0] = ctx->Stencil.ValueMask[1] = mask;
if (ctx->Driver.StencilFuncSeparate) {
ctx->Driver.StencilFuncSeparate(ctx,
((ctx->Stencil.TestTwoSide)
? GL_FRONT : GL_FRONT_AND_BACK),
func, ref, mask);
}
}
}
/**
* Set the stencil writing mask.
*
* \param mask bit-mask to enable/disable writing of individual bits in the
* stencil planes.
*
* \sa glStencilMask().
*
* Updates gl_stencil_attrib::WriteMask. On change flushes the vertices and
* notifies the driver via the dd_function_table::StencilMask callback.
*/
void GLAPIENTRY
_mesa_StencilMask( GLuint mask )
{
GET_CURRENT_CONTEXT(ctx);
const GLint face = ctx->Stencil.ActiveFace;
ASSERT_OUTSIDE_BEGIN_END(ctx);
if (face != 0) {
/* Only modify the EXT_stencil_two_side back-face state.
*/
if (ctx->Stencil.WriteMask[face] == mask)
return;
FLUSH_VERTICES(ctx, _NEW_STENCIL);
ctx->Stencil.WriteMask[face] = mask;
/* Only propagate the change to the driver if EXT_stencil_two_side
* is enabled.
*/
if (ctx->Driver.StencilMaskSeparate && ctx->Stencil.TestTwoSide) {
ctx->Driver.StencilMaskSeparate(ctx, GL_BACK, mask);
}
}
else {
/* set both front and back state */
if (ctx->Stencil.WriteMask[0] == mask &&
ctx->Stencil.WriteMask[1] == mask)
return;
FLUSH_VERTICES(ctx, _NEW_STENCIL);
ctx->Stencil.WriteMask[0] = ctx->Stencil.WriteMask[1] = mask;
if (ctx->Driver.StencilMaskSeparate) {
ctx->Driver.StencilMaskSeparate(ctx,
((ctx->Stencil.TestTwoSide)
? GL_FRONT : GL_FRONT_AND_BACK),
mask);
}
}
}
/**
* Set the stencil test actions.
*
* \param fail action to take when stencil test fails.
* \param zfail action to take when stencil test passes, but depth test fails.
* \param zpass action to take when stencil test passes and the depth test
* passes (or depth testing is not enabled).
*
* \sa glStencilOp().
*
* Verifies the parameters and updates the respective fields in
* __struct gl_contextRec::Stencil. On change flushes the vertices and notifies the
* driver via the dd_function_table::StencilOp callback.
*/
void GLAPIENTRY
_mesa_StencilOp(GLenum fail, GLenum zfail, GLenum zpass)
{
GET_CURRENT_CONTEXT(ctx);
const GLint face = ctx->Stencil.ActiveFace;
ASSERT_OUTSIDE_BEGIN_END(ctx);
if (!validate_stencil_op(ctx, fail)) {
_mesa_error(ctx, GL_INVALID_ENUM, "glStencilOp(sfail)");
return;
}
if (!validate_stencil_op(ctx, zfail)) {
_mesa_error(ctx, GL_INVALID_ENUM, "glStencilOp(zfail)");
return;
}
if (!validate_stencil_op(ctx, zpass)) {
_mesa_error(ctx, GL_INVALID_ENUM, "glStencilOp(zpass)");
return;
}
if (face != 0) {
/* only set active face state */
if (ctx->Stencil.ZFailFunc[face] == zfail &&
ctx->Stencil.ZPassFunc[face] == zpass &&
ctx->Stencil.FailFunc[face] == fail)
return;
FLUSH_VERTICES(ctx, _NEW_STENCIL);
ctx->Stencil.ZFailFunc[face] = zfail;
ctx->Stencil.ZPassFunc[face] = zpass;
ctx->Stencil.FailFunc[face] = fail;
/* Only propagate the change to the driver if EXT_stencil_two_side
* is enabled.
*/
if (ctx->Driver.StencilOpSeparate && ctx->Stencil.TestTwoSide) {
ctx->Driver.StencilOpSeparate(ctx, GL_BACK, fail, zfail, zpass);
}
}
else {
/* set both front and back state */
if (ctx->Stencil.ZFailFunc[0] == zfail &&
ctx->Stencil.ZFailFunc[1] == zfail &&
ctx->Stencil.ZPassFunc[0] == zpass &&
ctx->Stencil.ZPassFunc[1] == zpass &&
ctx->Stencil.FailFunc[0] == fail &&
ctx->Stencil.FailFunc[1] == fail)
return;
FLUSH_VERTICES(ctx, _NEW_STENCIL);
ctx->Stencil.ZFailFunc[0] = ctx->Stencil.ZFailFunc[1] = zfail;
ctx->Stencil.ZPassFunc[0] = ctx->Stencil.ZPassFunc[1] = zpass;
ctx->Stencil.FailFunc[0] = ctx->Stencil.FailFunc[1] = fail;
if (ctx->Driver.StencilOpSeparate) {
ctx->Driver.StencilOpSeparate(ctx,
((ctx->Stencil.TestTwoSide)
? GL_FRONT : GL_FRONT_AND_BACK),
fail, zfail, zpass);
}
}
}
#if _HAVE_FULL_GL
/* GL_EXT_stencil_two_side */
void GLAPIENTRY
_mesa_ActiveStencilFaceEXT(GLenum face)
{
GET_CURRENT_CONTEXT(ctx);
ASSERT_OUTSIDE_BEGIN_END(ctx);
if (!ctx->Extensions.EXT_stencil_two_side) {
_mesa_error(ctx, GL_INVALID_OPERATION, "glActiveStencilFaceEXT");
return;
}
if (face == GL_FRONT || face == GL_BACK) {
FLUSH_VERTICES(ctx, _NEW_STENCIL);
ctx->Stencil.ActiveFace = (face == GL_FRONT) ? 0 : 2;
}
else {
_mesa_error(ctx, GL_INVALID_ENUM, "glActiveStencilFaceEXT(face)");
}
}
#endif
/**
* OpenGL 2.0 function.
* \todo Make StencilOp() call this function. And eventually remove the
* ctx->Driver.StencilOp function and use ctx->Driver.StencilOpSeparate
* instead.
*/
void GLAPIENTRY
_mesa_StencilOpSeparate(GLenum face, GLenum sfail, GLenum zfail, GLenum zpass)
{
GLboolean set = GL_FALSE;
GET_CURRENT_CONTEXT(ctx);
ASSERT_OUTSIDE_BEGIN_END(ctx);
if (!validate_stencil_op(ctx, sfail)) {
_mesa_error(ctx, GL_INVALID_ENUM, "glStencilOpSeparate(sfail)");
return;
}
if (!validate_stencil_op(ctx, zfail)) {
_mesa_error(ctx, GL_INVALID_ENUM, "glStencilOpSeparate(zfail)");
return;
}
if (!validate_stencil_op(ctx, zpass)) {
_mesa_error(ctx, GL_INVALID_ENUM, "glStencilOpSeparate(zpass)");
return;
}
if (face != GL_FRONT && face != GL_BACK && face != GL_FRONT_AND_BACK) {
_mesa_error(ctx, GL_INVALID_ENUM, "glStencilOpSeparate(face)");
return;
}
if (face != GL_BACK) {
/* set front */
if (ctx->Stencil.ZFailFunc[0] != zfail ||
ctx->Stencil.ZPassFunc[0] != zpass ||
ctx->Stencil.FailFunc[0] != sfail){
FLUSH_VERTICES(ctx, _NEW_STENCIL);
ctx->Stencil.ZFailFunc[0] = zfail;
ctx->Stencil.ZPassFunc[0] = zpass;
ctx->Stencil.FailFunc[0] = sfail;
set = GL_TRUE;
}
}
if (face != GL_FRONT) {
/* set back */
if (ctx->Stencil.ZFailFunc[1] != zfail ||
ctx->Stencil.ZPassFunc[1] != zpass ||
ctx->Stencil.FailFunc[1] != sfail) {
FLUSH_VERTICES(ctx, _NEW_STENCIL);
ctx->Stencil.ZFailFunc[1] = zfail;
ctx->Stencil.ZPassFunc[1] = zpass;
ctx->Stencil.FailFunc[1] = sfail;
set = GL_TRUE;
}
}
if (set && ctx->Driver.StencilOpSeparate) {
ctx->Driver.StencilOpSeparate(ctx, face, sfail, zfail, zpass);
}
}
/* OpenGL 2.0 */
void GLAPIENTRY
_mesa_StencilFuncSeparate(GLenum face, GLenum func, GLint ref, GLuint mask)
{
GET_CURRENT_CONTEXT(ctx);
const GLint stencilMax = (1 << ctx->DrawBuffer->Visual.stencilBits) - 1;
ASSERT_OUTSIDE_BEGIN_END(ctx);
if (face != GL_FRONT && face != GL_BACK && face != GL_FRONT_AND_BACK) {
_mesa_error(ctx, GL_INVALID_ENUM, "glStencilFuncSeparate(face)");
return;
}
if (!validate_stencil_func(ctx, func)) {
_mesa_error(ctx, GL_INVALID_ENUM, "glStencilFuncSeparate(func)");
return;
}
ref = CLAMP(ref, 0, stencilMax);
FLUSH_VERTICES(ctx, _NEW_STENCIL);
if (face != GL_BACK) {
/* set front */
ctx->Stencil.Function[0] = func;
ctx->Stencil.Ref[0] = ref;
ctx->Stencil.ValueMask[0] = mask;
}
if (face != GL_FRONT) {
/* set back */
ctx->Stencil.Function[1] = func;
ctx->Stencil.Ref[1] = ref;
ctx->Stencil.ValueMask[1] = mask;
}
if (ctx->Driver.StencilFuncSeparate) {
ctx->Driver.StencilFuncSeparate(ctx, face, func, ref, mask);
}
}
/* OpenGL 2.0 */
void GLAPIENTRY
_mesa_StencilMaskSeparate(GLenum face, GLuint mask)
{
GET_CURRENT_CONTEXT(ctx);
ASSERT_OUTSIDE_BEGIN_END(ctx);
if (face != GL_FRONT && face != GL_BACK && face != GL_FRONT_AND_BACK) {
_mesa_error(ctx, GL_INVALID_ENUM, "glStencilaMaskSeparate(face)");
return;
}
FLUSH_VERTICES(ctx, _NEW_STENCIL);
if (face != GL_BACK) {
ctx->Stencil.WriteMask[0] = mask;
}
if (face != GL_FRONT) {
ctx->Stencil.WriteMask[1] = mask;
}
if (ctx->Driver.StencilMaskSeparate) {
ctx->Driver.StencilMaskSeparate(ctx, face, mask);
}
}
/**
* Update derived stencil state.
*/
void
_mesa_update_stencil(struct gl_context *ctx)
{
const GLint face = ctx->Stencil._BackFace;
ctx->Stencil._Enabled = (ctx->Stencil.Enabled &&
ctx->DrawBuffer->Visual.stencilBits > 0);
ctx->Stencil._TestTwoSide =
ctx->Stencil._Enabled &&
(ctx->Stencil.Function[0] != ctx->Stencil.Function[face] ||
ctx->Stencil.FailFunc[0] != ctx->Stencil.FailFunc[face] ||
ctx->Stencil.ZPassFunc[0] != ctx->Stencil.ZPassFunc[face] ||
ctx->Stencil.ZFailFunc[0] != ctx->Stencil.ZFailFunc[face] ||
ctx->Stencil.Ref[0] != ctx->Stencil.Ref[face] ||
ctx->Stencil.ValueMask[0] != ctx->Stencil.ValueMask[face] ||
ctx->Stencil.WriteMask[0] != ctx->Stencil.WriteMask[face]);
}
/**
* Initialize the context stipple state.
*
* \param ctx GL context.
*
* Initializes __struct gl_contextRec::Stencil attribute group.
*/
void
_mesa_init_stencil(struct gl_context *ctx)
{
ctx->Stencil.Enabled = GL_FALSE;
ctx->Stencil.TestTwoSide = GL_FALSE;
ctx->Stencil.ActiveFace = 0; /* 0 = GL_FRONT, 2 = GL_BACK */
ctx->Stencil.Function[0] = GL_ALWAYS;
ctx->Stencil.Function[1] = GL_ALWAYS;
ctx->Stencil.Function[2] = GL_ALWAYS;
ctx->Stencil.FailFunc[0] = GL_KEEP;
ctx->Stencil.FailFunc[1] = GL_KEEP;
ctx->Stencil.FailFunc[2] = GL_KEEP;
ctx->Stencil.ZPassFunc[0] = GL_KEEP;
ctx->Stencil.ZPassFunc[1] = GL_KEEP;
ctx->Stencil.ZPassFunc[2] = GL_KEEP;
ctx->Stencil.ZFailFunc[0] = GL_KEEP;
ctx->Stencil.ZFailFunc[1] = GL_KEEP;
ctx->Stencil.ZFailFunc[2] = GL_KEEP;
ctx->Stencil.Ref[0] = 0;
ctx->Stencil.Ref[1] = 0;
ctx->Stencil.Ref[2] = 0;
ctx->Stencil.ValueMask[0] = ~0U;
ctx->Stencil.ValueMask[1] = ~0U;
ctx->Stencil.ValueMask[2] = ~0U;
ctx->Stencil.WriteMask[0] = ~0U;
ctx->Stencil.WriteMask[1] = ~0U;
ctx->Stencil.WriteMask[2] = ~0U;
ctx->Stencil.Clear = 0;
ctx->Stencil._BackFace = 1;
}