mesa: Initialize image units to default state on context creation.

This is the required initial image unit state according to "Table 23.45. Image
State (state per image unit)" of the OpenGL 4.3 specification.

Reviewed-by: Matt Turner <[email protected]>

3 files changed, 21 insertions, 0 deletions

diff --git a/src/mesa/main/context.c b/src/mesa/main/context.c
index 4aaf8b1af57..0a192de8c0a 100644
--- a/src/mesa/main/context.c
+++ b/src/mesa/main/context.c
@@ -118,6 +118,7 @@
 #include "scissor.h"
 #include "shared.h"
 #include "shaderobj.h"
+#include "shaderimage.h"
 #include "util/simple_list.h"
 #include "state.h"
 #include "stencil.h"
@@ -821,6 +822,7 @@ init_attrib_groups(struct gl_context *ctx)
    _mesa_init_feedback( ctx );
    _mesa_init_fog( ctx );
    _mesa_init_hint( ctx );
+   _mesa_init_image_units( ctx );
    _mesa_init_line( ctx );
    _mesa_init_lighting( ctx );
    _mesa_init_matrix( ctx );
diff --git a/src/mesa/main/shaderimage.c b/src/mesa/main/shaderimage.c
index 8caff2f2660..efe439c6dfd 100644
--- a/src/mesa/main/shaderimage.c
+++ b/src/mesa/main/shaderimage.c
@@ -331,6 +331,19 @@ get_image_format_class(mesa_format format)
    }
 }
 
+void
+_mesa_init_image_units(struct gl_context *ctx)
+{
+   unsigned i;
+
+   for (i = 0; i < ARRAY_SIZE(ctx->ImageUnits); ++i) {
+      struct gl_image_unit *u = &ctx->ImageUnits[i];
+      u->Access = GL_READ_ONLY;
+      u->Format = GL_R8;
+      u->_ActualFormat = _mesa_get_shader_image_format(u->Format);
+   }
+}
+
 static GLboolean
 validate_image_unit(struct gl_context *ctx, struct gl_image_unit *u)
 {
diff --git a/src/mesa/main/shaderimage.h b/src/mesa/main/shaderimage.h
index 1c7d1e0e894..33d8a1eff55 100644
--- a/src/mesa/main/shaderimage.h
+++ b/src/mesa/main/shaderimage.h
@@ -43,6 +43,12 @@ mesa_format
 _mesa_get_shader_image_format(GLenum format);
 
 /**
+ * Initialize a context's shader image units to the default state.
+ */
+void
+_mesa_init_image_units(struct gl_context *ctx);
+
+/**
  * Recalculate the \c _Valid flag of a context's shader image units.
  *
  * To be called when the state of any texture bound to an image unit