text: Batch glyphs into one wish -- fixes performance.

2 files changed, 14 insertions, 1 deletions

diff --git a/virtual-programs/display.folk b/virtual-programs/display.folk
index 07b94825..387d300a 100644
--- a/virtual-programs/display.folk
+++ b/virtual-programs/display.folk
@@ -101,6 +101,8 @@ Start process "display" {
         [list /someone/ wishes the GPU compiles pipeline /name/ /source/]
     Wish $::thisProcess receives statements like \
         [list /someone/ wishes the GPU draws pipeline /name/ with arguments /args/]
+    Wish $::thisProcess receives statements like \
+        [list /someone/ wishes the GPU draws pipeline /name/ with instances /args/]
     Wish $::thisProcess shares statements like \
         [list /someone/ claims the display time is /displayTime/]
 
@@ -115,6 +117,12 @@ Start process "display" {
         foreach match [Statements::findMatches {/someone/ wishes the GPU draws pipeline /name/ with arguments /args/}] {
             lappend ::displayList [list Gpu::draw [dict get $::pipelines [dict get $match name]] {*}[dict get $match args]]
         }
+        foreach match [Statements::findMatches {/someone/ wishes the GPU draws pipeline /name/ with instances /instances/}] {
+            set pipeline [dict get $::pipelines [dict get $match name]]
+            foreach instance [dict get $match instances] {
+                lappend ::displayList [list Gpu::draw $pipeline {*}$instance]
+            }
+        }
 
         set renderTime [baretime {
             Gpu::drawStart
diff --git a/virtual-programs/display/text.folk b/virtual-programs/display/text.folk
index 992e77b1..a6c828b9 100644
--- a/virtual-programs/display/text.folk
+++ b/virtual-programs/display/text.folk
@@ -124,6 +124,7 @@ On process "display" {
         set x $x0; set y $y0
 
         set lineNum 0
+        set instances [list]
         for {set i 0} {$i < [string length $text]} {incr i} {
             set char [string index $text $i]
             if {$char eq "\n"} {
@@ -140,12 +141,16 @@ On process "display" {
             }
             lassign $glyphInfo advance planeBounds atlasBounds
             if {$char ne " "} {
-                Wish the GPU draws pipeline "glyph" with arguments \
+                lappend instances \
                     [list $fontAtlas $fontAtlasSize \
                          $atlasBounds $planeBounds [list $x $y] $radians $em]
             }
             lassign [vec2 add [list $x $y] \
                          [vec2 rotate [list [* $advance $em] 0] $radians]] x y
         }
+
+        # We need to batch into one wish so we don't deal with n^2
+        # checks for existing statements for n glyphs.
+        Wish the GPU draws pipeline "glyph" with instances $instances
     }
 }