Mesa (master): i965: Normalize cubemap coordinates like is done in the Mesa IR path.

[Eric Anholt]

Module: Mesa
Branch: master
Commit: bbb840049e7a92af6e0e8c2c5c21c63caec9e826
URL:    http://cgit.freedesktop.org/mesa/mesa/commit/?id=bbb840049e7a92af6e0e8c2c5c21c63caec9e826

Author: Eric Anholt <eric at anholt.net>
Date:   Tue Oct  5 22:30:42 2010 -0700

i965: Normalize cubemap coordinates like is done in the Mesa IR path.

Fixes glsl-fs-texturecube-2-*

---

 src/mesa/drivers/dri/i965/Makefile                 |    1 +
 src/mesa/drivers/dri/i965/brw_context.h            |    2 +
 .../drivers/dri/i965/brw_cubemap_normalize.cpp     |  110 ++++++++++++++++++++
 src/mesa/drivers/dri/i965/brw_fs.cpp               |    1 +
 4 files changed, 114 insertions(+), 0 deletions(-)

diff --git a/src/mesa/drivers/dri/i965/Makefile b/src/mesa/drivers/dri/i965/Makefile
index bea48e1..917d390 100644
--- a/src/mesa/drivers/dri/i965/Makefile
+++ b/src/mesa/drivers/dri/i965/Makefile
@@ -105,6 +105,7 @@ C_SOURCES = \
 	$(DRIVER_SOURCES)
 
 CXX_SOURCES = \
+	brw_cubemap_normalize.cpp \
 	brw_fs.cpp \
 	brw_fs_channel_expressions.cpp \
 	brw_fs_vector_splitting.cpp
diff --git a/src/mesa/drivers/dri/i965/brw_context.h b/src/mesa/drivers/dri/i965/brw_context.h
index 703a7de..71e6d8e 100644
--- a/src/mesa/drivers/dri/i965/brw_context.h
+++ b/src/mesa/drivers/dri/i965/brw_context.h
@@ -800,5 +800,7 @@ brw_fragment_program_const(const struct gl_fragment_program *p)
    return (const struct brw_fragment_program *) p;
 }
 
+GLboolean brw_do_cubemap_normalize(struct exec_list *instructions);
+
 #endif
 
diff --git a/src/mesa/drivers/dri/i965/brw_cubemap_normalize.cpp b/src/mesa/drivers/dri/i965/brw_cubemap_normalize.cpp
new file mode 100644
index 0000000..35bea68
--- /dev/null
+++ b/src/mesa/drivers/dri/i965/brw_cubemap_normalize.cpp
@@ -0,0 +1,110 @@
+/*
+ * Copyright © 2010 Intel Corporation
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice (including the next
+ * paragraph) shall be included in all copies or substantial portions of the
+ * Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
+ * DEALINGS IN THE SOFTWARE.
+ */
+
+/**
+ * \file brw_cubemap_normalize.cpp
+ *
+ * IR lower pass to perform the normalization of the cubemap coordinates to
+ * have the largest magnitude component be -1.0 or 1.0.
+ *
+ * \author Eric Anholt <eric at anholt.net>
+ */
+
+#include "../glsl/glsl_types.h"
+#include "../glsl/ir.h"
+
+class brw_cubemap_normalize_visitor : public ir_hierarchical_visitor {
+public:
+   brw_cubemap_normalize_visitor()
+   {
+      progress = false;
+   }
+
+   ir_visitor_status visit_leave(ir_texture *ir);
+
+   bool progress;
+};
+
+ir_visitor_status
+brw_cubemap_normalize_visitor::visit_leave(ir_texture *ir)
+{
+   if (ir->sampler->type->sampler_dimensionality != GLSL_SAMPLER_DIM_CUBE)
+      return visit_continue;
+
+   void *mem_ctx = talloc_parent(ir);
+
+   ir_variable *var = new(mem_ctx) ir_variable(ir->coordinate->type,
+					       "coordinate", ir_var_auto);
+   base_ir->insert_before(var);
+   ir_dereference *deref = new(mem_ctx) ir_dereference_variable(var);
+   ir_assignment *assign = new(mem_ctx) ir_assignment(deref, ir->coordinate,
+						      NULL);
+   base_ir->insert_before(assign);
+
+   deref = new(mem_ctx) ir_dereference_variable(var);
+   ir_rvalue *swiz0 = new(mem_ctx) ir_swizzle(deref, 0, 0, 0, 0, 1);
+   deref = new(mem_ctx) ir_dereference_variable(var);
+   ir_rvalue *swiz1 = new(mem_ctx) ir_swizzle(deref, 1, 0, 0, 0, 1);
+   deref = new(mem_ctx) ir_dereference_variable(var);
+   ir_rvalue *swiz2 = new(mem_ctx) ir_swizzle(deref, 2, 0, 0, 0, 1);
+
+   swiz0 = new(mem_ctx) ir_expression(ir_unop_abs, swiz0->type, swiz0, NULL);
+   swiz1 = new(mem_ctx) ir_expression(ir_unop_abs, swiz1->type, swiz1, NULL);
+   swiz2 = new(mem_ctx) ir_expression(ir_unop_abs, swiz2->type, swiz2, NULL);
+
+   ir_expression *expr;
+   expr = new(mem_ctx) ir_expression(ir_binop_max,
+				     glsl_type::float_type,
+				     swiz0, swiz1);
+
+   expr = new(mem_ctx) ir_expression(ir_binop_max,
+				     glsl_type::float_type,
+				     expr, swiz2);
+
+   expr = new(mem_ctx) ir_expression(ir_unop_rcp,
+				     glsl_type::float_type,
+				     expr, NULL);
+
+   deref = new(mem_ctx) ir_dereference_variable(var);
+   ir->coordinate = new(mem_ctx) ir_expression(ir_binop_mul,
+					       ir->coordinate->type,
+					       deref,
+					       expr);
+
+   progress = true;
+   return visit_continue;
+}
+
+extern "C" {
+
+GLboolean
+brw_do_cubemap_normalize(exec_list *instructions)
+{
+   brw_cubemap_normalize_visitor v;
+
+   visit_list_elements(&v, instructions);
+
+   return v.progress;
+}
+
+}
diff --git a/src/mesa/drivers/dri/i965/brw_fs.cpp b/src/mesa/drivers/dri/i965/brw_fs.cpp
index 0b342c2..710eb0b 100644
--- a/src/mesa/drivers/dri/i965/brw_fs.cpp
+++ b/src/mesa/drivers/dri/i965/brw_fs.cpp
@@ -140,6 +140,7 @@ brw_link_shader(GLcontext *ctx, struct gl_shader_program *prog)
 	 do_sub_to_add_neg(shader->ir);
 	 do_explog_to_explog2(shader->ir);
 	 do_lower_texture_projection(shader->ir);
+	 brw_do_cubemap_normalize(shader->ir);
 
 	 do {
 	    progress = false;