Fix T36165: blender internal HDR textures with negative values got clamped.

For example for vector displacement, you may have an EXR texture that has
negative colors values. Blender clamps these by default, now the Colors panel
for textures has a Clamp option to disable this clamping.

This option affects all texture types and is enabled by default, you need
to disable it if you want negative values to have an influence.

Patch by Fredrik Hansson with modifications by me.

1 files changed, 5 insertions, 0 deletions

diff --git a/source/blender/makesrna/intern/rna_texture.c b/source/blender/makesrna/intern/rna_texture.c
index b453965d21f..37a0ee0da8e 100644
--- a/source/blender/makesrna/intern/rna_texture.c
+++ b/source/blender/makesrna/intern/rna_texture.c
@@ -2010,6 +2010,11 @@ static void rna_def_texture(BlenderRNA *brna)
 	RNA_def_property_enum_funcs(prop, NULL, "rna_Texture_type_set", NULL);
 	RNA_def_property_ui_text(prop, "Type", "");
 	RNA_def_property_update(prop, 0, "rna_Texture_update");
+
+	prop = RNA_def_property(srna, "use_clamp", PROP_BOOLEAN, PROP_NONE);
+	RNA_def_property_boolean_negative_sdna(prop, NULL, "flag", TEX_NO_CLAMP);
+	RNA_def_property_ui_text(prop, "Clamp", "Set negative texture RGB and intensity values to zero, for some uses like displacement this option can be disabled to get the full range");
+	RNA_def_property_update(prop, 0, "rna_Texture_update");
 	
 	prop = RNA_def_property(srna, "use_color_ramp", PROP_BOOLEAN, PROP_NONE);
 	RNA_def_property_boolean_sdna(prop, NULL, "flag", TEX_COLORBAND);