diff options
Diffstat (limited to 'src/mesa/main/rastpos.c')
| -rw-r--r-- | src/mesa/main/rastpos.c | 55 |
1 files changed, 46 insertions, 9 deletions
diff --git a/src/mesa/main/rastpos.c b/src/mesa/main/rastpos.c index 1ca83c78b0a..0308003905b 100644 --- a/src/mesa/main/rastpos.c +++ b/src/mesa/main/rastpos.c @@ -61,16 +61,35 @@ viewclip_point_xy( const GLfloat v[] ) /** - * Clip a point against the far/near Z clipping planes. + * Clip a point against the near Z clipping planes. * * \param v vertex vector describing the point to clip. * * \return zero if outside view volume, or one if inside. */ static GLuint -viewclip_point_z( const GLfloat v[] ) +viewclip_point_near_z( const GLfloat v[] ) { - if (v[2] > v[3] || v[2] < -v[3] ) { + if (v[2] < -v[3]) { + return 0; + } + else { + return 1; + } +} + + +/** + * Clip a point against the far Z clipping planes. + * + * \param v vertex vector describing the point to clip. + * + * \return zero if outside view volume, or one if inside. + */ +static GLuint +viewclip_point_far_z( const GLfloat v[] ) +{ + if (v[2] > v[3]) { return 0; } else { @@ -389,8 +408,14 @@ _mesa_RasterPos(struct gl_context *ctx, const GLfloat vObj[4]) TRANSFORM_POINT( clip, ctx->ProjectionMatrixStack.Top->m, eye ); /* clip to view volume. */ - if (!ctx->Transform.DepthClamp) { - if (viewclip_point_z(clip) == 0) { + if (!ctx->Transform.DepthClampNear) { + if (viewclip_point_near_z(clip) == 0) { + ctx->Current.RasterPosValid = GL_FALSE; + return; + } + } + if (!ctx->Transform.DepthClampFar) { + if (viewclip_point_far_z(clip) == 0) { ctx->Current.RasterPosValid = GL_FALSE; return; } @@ -420,10 +445,22 @@ _mesa_RasterPos(struct gl_context *ctx, const GLfloat vObj[4]) ctx->Current.RasterPos[2] = ndc[2] * scale[2] + translate[2]; ctx->Current.RasterPos[3] = clip[3]; - if (ctx->Transform.DepthClamp) { - ctx->Current.RasterPos[3] = CLAMP(ctx->Current.RasterPos[3], - ctx->ViewportArray[0].Near, - ctx->ViewportArray[0].Far); + if (ctx->Transform.DepthClampNear && + ctx->Transform.DepthClampFar) { + ctx->Current.RasterPos[3] = CLAMP(ctx->Current.RasterPos[3], + ctx->ViewportArray[0].Near, + ctx->ViewportArray[0].Far); + } else { + /* Clamp against near and far plane separately */ + if (ctx->Transform.DepthClampNear) { + ctx->Current.RasterPos[3] = MAX2(ctx->Current.RasterPos[3], + ctx->ViewportArray[0].Near); + } + + if (ctx->Transform.DepthClampFar) { + ctx->Current.RasterPos[3] = MIN2(ctx->Current.RasterPos[3], + ctx->ViewportArray[0].Far); + } } /* compute raster distance */ |