Cycles: Add single channel texture support for OpenCL.

This way OpenCL devices can also benefit from a smaller memory footprint, when using e.g. bumpmaps (greyscale, 1 channel).

Additional target for my GSoC 2016.

3 files changed, 18 insertions, 2 deletions

diff --git a/intern/cycles/kernel/kernel_compat_cpu.h b/intern/cycles/kernel/kernel_compat_cpu.h
index c882b477c35..3775934f293 100644
--- a/intern/cycles/kernel/kernel_compat_cpu.h
+++ b/intern/cycles/kernel/kernel_compat_cpu.h
@@ -495,6 +495,7 @@ typedef texture<uint> texture_uint;
 typedef texture<int> texture_int;
 typedef texture<uint4> texture_uint4;
 typedef texture<uchar4> texture_uchar4;
+typedef texture<uchar> texture_uchar;
 typedef texture_image<float> texture_image_float;
 typedef texture_image<uchar> texture_image_uchar;
 typedef texture_image<half> texture_image_half;
diff --git a/intern/cycles/kernel/kernel_textures.h b/intern/cycles/kernel/kernel_textures.h
index 7d6fec02331..8d5bb75a428 100644
--- a/intern/cycles/kernel/kernel_textures.h
+++ b/intern/cycles/kernel/kernel_textures.h
@@ -188,6 +188,8 @@ KERNEL_TEX(uint, texture_uint, __bindless_mapping)
 /* packed image (opencl) */
 KERNEL_TEX(uchar4, texture_uchar4, __tex_image_byte4_packed)
 KERNEL_TEX(float4, texture_float4, __tex_image_float4_packed)
+KERNEL_TEX(uchar, texture_uchar, __tex_image_byte_packed)
+KERNEL_TEX(float, texture_float, __tex_image_float_packed)
 KERNEL_TEX(uint4, texture_uint4, __tex_image_packed_info)
 
 #undef KERNEL_TEX
diff --git a/intern/cycles/kernel/svm/svm_image.h b/intern/cycles/kernel/svm/svm_image.h
index 9050ce93951..5d02be1fa2f 100644
--- a/intern/cycles/kernel/svm/svm_image.h
+++ b/intern/cycles/kernel/svm/svm_image.h
@@ -36,13 +36,26 @@ CCL_NAMESPACE_BEGIN
 
 ccl_device_inline float4 svm_image_texture_read(KernelGlobals *kg, int id, int offset)
 {
-	if(id >= TEX_NUM_FLOAT4_IMAGES) {
+	/* Float4 */
+	if(id < TEX_START_BYTE4_OPENCL) {
+		return kernel_tex_fetch(__tex_image_float4_packed, offset);
+	}
+	/* Byte4 */
+	else if(id < TEX_START_FLOAT_OPENCL) {
 		uchar4 r = kernel_tex_fetch(__tex_image_byte4_packed, offset);
 		float f = 1.0f/255.0f;
 		return make_float4(r.x*f, r.y*f, r.z*f, r.w*f);
 	}
+	/* Float */
+	else if(id < TEX_START_BYTE_OPENCL) {
+		float f = kernel_tex_fetch(__tex_image_float_packed, offset);
+		return make_float4(f, f, f, 1.0f);
+	}
+	/* Byte */
 	else {
-		return kernel_tex_fetch(__tex_image_float4_packed, offset);
+		uchar r = kernel_tex_fetch(__tex_image_byte_packed, offset);
+		float f = r * (1.0f/255.0f);
+		return make_float4(f, f, f, 1.0f);
 	}
 }