DRW-Next: Add uniform attributes (object attributes) support

This replaces the direct shader uniform layout declaration by a linear
search through a global buffer.

Each instance has an attribute offset inside the global buffer and an
attribute count.

This removes any padding and tighly pack all uniform attributes inside
a single buffer.

This would also remove the limit of 8 attribute but it is kept because of
compatibility with the old system that is still used by the old draw
manager.

1 files changed, 5 insertions, 5 deletions

diff --git a/source/blender/gpu/intern/gpu_codegen.cc b/source/blender/gpu/intern/gpu_codegen.cc
index d58ede4ccd8..f774f33e03d 100644
--- a/source/blender/gpu/intern/gpu_codegen.cc
+++ b/source/blender/gpu/intern/gpu_codegen.cc
@@ -199,8 +199,7 @@ static std::ostream &operator<<(std::ostream &stream, const GPUOutput *output)
 }
 
 /* Trick type to change overload and keep a somewhat nice syntax. */
-struct GPUConstant : public GPUInput {
-};
+struct GPUConstant : public GPUInput {};
 
 /* Print data constructor (i.e: vec2(1.0f, 1.0f)). */
 static std::ostream &operator<<(std::ostream &stream, const GPUConstant *input)
@@ -208,9 +207,10 @@ static std::ostream &operator<<(std::ostream &stream, const GPUConstant *input)
   stream << input->type << "(";
   for (int i = 0; i < input->type; i++) {
     char formated_float[32];
-    /* Print with the maximum precision for single precision float using scientific notation.
-     * See https://stackoverflow.com/questions/16839658/#answer-21162120 */
-    SNPRINTF(formated_float, "%.9g", input->vec[i]);
+    /* Use uint representation to allow exact same bit pattern even if NaN. This is because we can
+     * pass UINTs as floats for constants. */
+    const uint32_t *uint_vec = reinterpret_cast<const uint32_t *>(input->vec);
+    SNPRINTF(formated_float, "uintBitsToFloat(%uu)", uint_vec[i]);
     stream << formated_float;
     if (i < input->type - 1) {
       stream << ", ";