nir/linker: Fix TRANSFORM_FEEDBACK_BUFFER_INDEX

From the ARB_enhanced_layouts specification:

  "For the property TRANSFORM_FEEDBACK_BUFFER_INDEX, a single integer
   identifying the index of the active transform feedback buffer
   associated with an active variable is written to <params>.  For
   variables corresponding to the special names "gl_NextBuffer",
   "gl_SkipComponents1", "gl_SkipComponents2", "gl_SkipComponents3",
   and "gl_SkipComponents4", -1 is written to <params>."

We were storing the xfb_buffer value, instead of the value
corresponding to GL_TRANSFORM_FEEDBACK_BUFFER_INDEX.

Note that the implementation assumes that varyings would be sorted by
offset and buffer.

Signed-off-by: Antia Puentes <apuentes@igalia.com>
Signed-off-by: Alejandro Piñeiro <apinheiro@igalia.com>

Reviewed-by: Timothy Arceri <tarceri@itsqueeze.com>
This commit is contained in:
Antia Puentes
2018-12-22 18:40:29 +01:00
committed by Alejandro Piñeiro
parent 7c0f411c27
commit de31fb2f4f

View File

@@ -110,6 +110,11 @@ gl_nir_link_assign_xfb_resources(struct gl_context *ctx,
xfb_info->varying_count); xfb_info->varying_count);
linked_xfb->NumVarying = xfb_info->varying_count; linked_xfb->NumVarying = xfb_info->varying_count;
int buffer_index = 0; /* Corresponds to GL_TRANSFORM_FEEDBACK_BUFFER_INDEX */
int xfb_buffer =
(xfb_info->varying_count > 0) ?
xfb_info->outputs[0].buffer : 0;
for (unsigned i = 0; i < xfb_info->varying_count; i++) { for (unsigned i = 0; i < xfb_info->varying_count; i++) {
nir_xfb_varying_info *xfb_varying = &xfb_info->varyings[i]; nir_xfb_varying_info *xfb_varying = &xfb_info->varyings[i];
@@ -139,13 +144,18 @@ gl_nir_link_assign_xfb_resources(struct gl_context *ctx,
*/ */
prog->TransformFeedback.VaryingNames[i] = NULL; prog->TransformFeedback.VaryingNames[i] = NULL;
if (xfb_buffer != xfb_varying->buffer) {
buffer_index++;
xfb_buffer = xfb_varying->buffer;
}
struct gl_transform_feedback_varying_info *varying = struct gl_transform_feedback_varying_info *varying =
linked_xfb->Varyings + i; linked_xfb->Varyings + i;
/* ARB_gl_spirv: see above. */ /* ARB_gl_spirv: see above. */
varying->Name = NULL; varying->Name = NULL;
varying->Type = glsl_get_gl_type(xfb_varying->type); varying->Type = glsl_get_gl_type(xfb_varying->type);
varying->BufferIndex = xfb_varying->buffer; varying->BufferIndex = buffer_index;
varying->Size = glsl_get_length(xfb_varying->type); varying->Size = glsl_get_length(xfb_varying->type);
varying->Offset = xfb_varying->offset; varying->Offset = xfb_varying->offset;
} }