From d7052f6250ec5f825b8656e4e3650f988b49b355 Mon Sep 17 00:00:00 2001
From: SamGondelman <samuel_gondelman@brown.edu>
Date: Wed, 3 Aug 2016 16:27:51 -0700
Subject: [PATCH] try to make text entities fade

---
 .../entities-renderer/src/RenderableTextEntityItem.cpp | 10 +++++-----
 .../entities-renderer/src/RenderableTextEntityItem.h   |  4 ++++
 libraries/render-utils/src/sdf_text3D.slf              |  2 +-
 3 files changed, 10 insertions(+), 6 deletions(-)

diff --git a/libraries/entities-renderer/src/RenderableTextEntityItem.cpp b/libraries/entities-renderer/src/RenderableTextEntityItem.cpp
index 7f2644a68e..11c5f21a59 100644
--- a/libraries/entities-renderer/src/RenderableTextEntityItem.cpp
+++ b/libraries/entities-renderer/src/RenderableTextEntityItem.cpp
@@ -15,8 +15,6 @@
 #include <PerfStat.h>
 #include <Transform.h>
 
-
-
 #include "RenderableTextEntityItem.h"
 #include "GLMHelpers.h"
 
@@ -31,8 +29,10 @@ void RenderableTextEntityItem::render(RenderArgs* args) {
     Q_ASSERT(getType() == EntityTypes::Text);
     
     static const float SLIGHTLY_BEHIND = -0.005f;
-    glm::vec4 textColor = glm::vec4(toGlm(getTextColorX()), 1.0f);
-    glm::vec4 backgroundColor = glm::vec4(toGlm(getBackgroundColorX()), 1.0f);
+    float fadeRatio = Interpolate::calculateFadeRatio(_fadeStartTime);
+    bool transparent = fadeRatio < 1.0f;
+    glm::vec4 textColor = glm::vec4(toGlm(getTextColorX()), fadeRatio);
+    glm::vec4 backgroundColor = glm::vec4(toGlm(getBackgroundColorX()), fadeRatio);
     glm::vec3 dimensions = getDimensions();
     
     // Render background
@@ -62,7 +62,7 @@ void RenderableTextEntityItem::render(RenderArgs* args) {
     
     batch.setModelTransform(transformToTopLeft);
     
-    DependencyManager::get<GeometryCache>()->bindSimpleProgram(batch, false, false, false, false, true);
+    DependencyManager::get<GeometryCache>()->bindSimpleProgram(batch, false, transparent, false, false, true);
     DependencyManager::get<GeometryCache>()->renderQuad(batch, minCorner, maxCorner, backgroundColor);
     
     float scale = _lineHeight / _textRenderer->getFontSize();
diff --git a/libraries/entities-renderer/src/RenderableTextEntityItem.h b/libraries/entities-renderer/src/RenderableTextEntityItem.h
index cbe2b11c27..e0ddcad266 100644
--- a/libraries/entities-renderer/src/RenderableTextEntityItem.h
+++ b/libraries/entities-renderer/src/RenderableTextEntityItem.h
@@ -14,6 +14,7 @@
 
 #include <TextEntityItem.h>
 #include <TextRenderer3D.h>
+#include <Interpolate.h>
 
 #include "RenderableEntityItem.h"
 
@@ -27,10 +28,13 @@ public:
 
     virtual void render(RenderArgs* args) override;
 
+    bool isTransparent() override { return Interpolate::calculateFadeRatio(_fadeStartTime) < 1.0f; }
+
     SIMPLE_RENDERABLE();
     
 private:
     TextRenderer3D* _textRenderer = TextRenderer3D::getInstance(SANS_FONT_FAMILY, FIXED_FONT_POINT_SIZE / 2.0f);
+    quint64 _fadeStartTime { usecTimestampNow() };
 };
 
 
diff --git a/libraries/render-utils/src/sdf_text3D.slf b/libraries/render-utils/src/sdf_text3D.slf
index f5385c23b7..f578895c85 100644
--- a/libraries/render-utils/src/sdf_text3D.slf
+++ b/libraries/render-utils/src/sdf_text3D.slf
@@ -48,7 +48,7 @@ void main() {
     
     packDeferredFragmentTranslucent(
         normalize(_normal),
-        a,
+        a * Color.a,
         Color.rgb,
         DEFAULT_FRESNEL,
         DEFAULT_ROUGHNESS);