Add support for multiple interpolation modes on cycles image textures

All textures are sampled bi-linear currently with the exception of OSL there texture sampling is fixed and set to smart bi-cubic.

This patch adds user control to this setting.

Added:
- bits to DNA / RNA in the form of an enum for supporting multiple interpolations types
- changes to the image texture node drawing code ( add enum)
- to ImageManager (this needs to know to allocate second texture when interpolation type is different)
- to node compiler (pass on interpolation type)
- to device tex_alloc this also needs to get the concept of multiple interpolation types
- implementation for doing non interpolated lookup for cuda and cpu
- implementation where we pass this along to osl ( this makes OSL also do linear untill I add smartcubic to the interface / DNA/ RNA)

Reviewers: brecht, dingto

Reviewed By: brecht

CC: dingto, venomgfx

Differential Revision: https://developer.blender.org/D317

1 files changed, 10 insertions, 0 deletions

diff --git a/intern/cycles/util/util_types.h b/intern/cycles/util/util_types.h
index 20d575e481c..5d2037960fc 100644
--- a/intern/cycles/util/util_types.h
+++ b/intern/cycles/util/util_types.h
@@ -450,6 +450,16 @@ ccl_device_inline int4 make_int4(const float3& f)
 
 #endif
 
+/* Interpolation types for textures
+ * cuda also use texture space to store other objects */
+enum InterpolationType {
+	INTERPOLATION_NONE = -1,
+	INTERPOLATION_LINEAR = 0,
+	INTERPOLATION_CLOSEST = 1,
+	INTERPOLATION_CUBIC = 2,
+	INTERPOLATION_SMART = 3,
+};
+
 CCL_NAMESPACE_END
 
 #endif /* __UTIL_TYPES_H__ */