[gtk/half-float: 8/11] ngl: Use a constant for (fp16)-1

[Matthias Clasen <matthiasc src gnome org>]

commit 7fe7b7ac7d260fedd7bb4485047be6cf2a738d83
Author: Matthias Clasen <mclasen redhat com>
Date:   Tue Apr 6 23:11:27 2021 -0400

    ngl: Use a constant for (fp16)-1
    
    No need to convert that again for every glyph.

 gsk/ngl/fp16private.h     | 2 ++
 gsk/ngl/gsknglrenderjob.c | 6 ++----
 2 files changed, 4 insertions(+), 4 deletions(-)
---
diff --git a/gsk/ngl/fp16private.h b/gsk/ngl/fp16private.h
index b285bf450c..3f74605288 100644
--- a/gsk/ngl/fp16private.h
+++ b/gsk/ngl/fp16private.h
@@ -30,6 +30,8 @@
 
 G_BEGIN_DECLS
 
+#define FP16_MINUS_ONE ((guint16)48128)
+
 #ifdef GRAPHENE_USE_SSE
 
 static inline void
diff --git a/gsk/ngl/gsknglrenderjob.c b/gsk/ngl/gsknglrenderjob.c
index 3f03148a84..56832efeea 100644
--- a/gsk/ngl/gsknglrenderjob.c
+++ b/gsk/ngl/gsknglrenderjob.c
@@ -2714,7 +2714,7 @@ gsk_ngl_render_job_visit_text_node (GskNglRenderJob     *job,
   guint last_texture = 0;
   GskNglDrawVertex *vertices;
   guint used = 0;
-  guint16 c[4];
+  guint16 c[4] = { FP16_MINUS_ONE, FP16_MINUS_ONE, FP16_MINUS_ONE, FP16_MINUS_ONE };
   const PangoGlyphInfo *gi;
   guint i;
   int yshift;
@@ -2726,9 +2726,7 @@ gsk_ngl_render_job_visit_text_node (GskNglRenderJob     *job,
   /* If the font has color glyphs, we don't need to recolor anything.
    * We tell the shader by setting the color to vec4(-1).
    */
-  if (!force_color && gsk_text_node_has_color_glyphs (node))
-    rgba_to_half (&(GdkRGBA){ -1.f, -1.f, -1.f, -1.f }, c);
-  else
+  if (force_color || !gsk_text_node_has_color_glyphs (node))
     rgba_to_half (color, c);
 
   lookup.font = (PangoFont *)font;