diff options
| -rw-r--r-- | src/mesa/main/mtypes.h | 2 | ||||
| -rw-r--r-- | src/mesa/main/stencil.c | 19 |
2 files changed, 19 insertions, 2 deletions
diff --git a/src/mesa/main/mtypes.h b/src/mesa/main/mtypes.h index 3c3214490a1..235d6b6bb54 100644 --- a/src/mesa/main/mtypes.h +++ b/src/mesa/main/mtypes.h @@ -1133,7 +1133,7 @@ struct gl_stencil_attrib GLboolean TestTwoSide; /**< GL_EXT_stencil_two_side */ GLubyte ActiveFace; /**< GL_EXT_stencil_two_side (0 or 2) */ GLboolean _TestTwoSide; - GLubyte _BackFace; + GLubyte _BackFace; /**< Current back stencil state (1 or 2) */ GLenum Function[3]; /**< Stencil function */ GLenum FailFunc[3]; /**< Fail function */ GLenum ZPassFunc[3]; /**< Depth buffer pass function */ diff --git a/src/mesa/main/stencil.c b/src/mesa/main/stencil.c index 6d6bbb2286b..e4a255d0a7e 100644 --- a/src/mesa/main/stencil.c +++ b/src/mesa/main/stencil.c @@ -27,6 +27,23 @@ * \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. */ @@ -542,7 +559,7 @@ _mesa_init_stencil(GLcontext *ctx) { ctx->Stencil.Enabled = GL_FALSE; ctx->Stencil.TestTwoSide = GL_FALSE; - ctx->Stencil.ActiveFace = 0; /* 0 = GL_FRONT, 1 = GL_BACK */ + 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; |