From e36ff0d238f0fb16a6d211343cb5c07ae56bf2fb Mon Sep 17 00:00:00 2001
From: Andrzej Kapolka <drzej.k@gmail.com>
Date: Fri, 12 Sep 2014 18:56:07 -0700
Subject: [PATCH] Fix deferred lighting for rear view mirror.

---
 interface/src/Application.cpp                    |  4 ++--
 .../src/renderer/DeferredLightingEffect.cpp      | 16 ++++++++++------
 interface/src/renderer/RenderUtil.cpp            | 10 +++++-----
 interface/src/renderer/RenderUtil.h              |  4 ++--
 4 files changed, 19 insertions(+), 15 deletions(-)

diff --git a/interface/src/Application.cpp b/interface/src/Application.cpp
index c657471f40..b507f3d346 100644
--- a/interface/src/Application.cpp
+++ b/interface/src/Application.cpp
@@ -695,8 +695,6 @@ void Application::paintGL() {
         displaySide(whichCamera);
         glPopMatrix();
 
-        _glowEffect.render();
-
         if (Menu::getInstance()->isOptionChecked(MenuOption::Mirror)) {
             renderRearViewMirror(_mirrorViewRect);
 
@@ -704,6 +702,8 @@ void Application::paintGL() {
             _rearMirrorTools->render(true);
         }
 
+        _glowEffect.render();
+
         {
             PerformanceTimer perfTimer("renderOverlay");
             // PrioVR will only work if renderOverlay is called, calibration is connected to Application::renderingOverlay() 
diff --git a/interface/src/renderer/DeferredLightingEffect.cpp b/interface/src/renderer/DeferredLightingEffect.cpp
index 987de96d68..1bfec70db6 100644
--- a/interface/src/renderer/DeferredLightingEffect.cpp
+++ b/interface/src/renderer/DeferredLightingEffect.cpp
@@ -72,9 +72,13 @@ void DeferredLightingEffect::render() {
     int viewport[4];
     glGetIntegerv(GL_VIEWPORT, viewport);
     const int VIEWPORT_X_INDEX = 0;
+    const int VIEWPORT_Y_INDEX = 1;
     const int VIEWPORT_WIDTH_INDEX = 2;
+    const int VIEWPORT_HEIGHT_INDEX = 3;
     float sMin = viewport[VIEWPORT_X_INDEX] / (float)primaryFBO->width();
     float sWidth = viewport[VIEWPORT_WIDTH_INDEX] / (float)primaryFBO->width();
+    float tMin = viewport[VIEWPORT_Y_INDEX] / (float)primaryFBO->height();
+    float tHeight = viewport[VIEWPORT_HEIGHT_INDEX] / (float)primaryFBO->height();
    
     ProgramObject* program = &_directionalLight;
     const LightLocations* locations = &_directionalLightLocations;
@@ -109,13 +113,13 @@ void DeferredLightingEffect::render() {
     program->setUniformValue(locations->nearLocation, nearVal);
     program->setUniformValue(locations->depthScale, (farVal - nearVal) / farVal);
     float nearScale = -1.0f / nearVal;
-    float sScale = 1.0f / sWidth;
-    float depthTexCoordScaleS = (right - left) * nearScale * sScale;
+    float depthTexCoordScaleS = (right - left) * nearScale / sWidth;
+    float depthTexCoordScaleT = (top - bottom) * nearScale / tHeight;
     program->setUniformValue(locations->depthTexCoordOffset, left * nearScale - sMin * depthTexCoordScaleS,
-        bottom * nearScale);
-    program->setUniformValue(locations->depthTexCoordScale, depthTexCoordScaleS, (top - bottom) * nearScale);
+        bottom * nearScale - tMin * depthTexCoordScaleT);
+    program->setUniformValue(locations->depthTexCoordScale, depthTexCoordScaleS, depthTexCoordScaleT);
     
-    renderFullscreenQuad(sMin, sMin + sWidth);
+    renderFullscreenQuad(sMin, sMin + sWidth, tMin, tMin + tHeight);
     
     program->release();
     
@@ -145,7 +149,7 @@ void DeferredLightingEffect::render() {
     glBindTexture(GL_TEXTURE_2D, freeFBO->texture());
     glEnable(GL_TEXTURE_2D);
     
-    renderFullscreenQuad(sMin, sMin + sWidth);
+    renderFullscreenQuad(sMin, sMin + sWidth, tMin, tMin + tHeight);
     
     glBindTexture(GL_TEXTURE_2D, 0);
     glDisable(GL_TEXTURE_2D);
diff --git a/interface/src/renderer/RenderUtil.cpp b/interface/src/renderer/RenderUtil.cpp
index 0575ceaa88..c2f05d373e 100644
--- a/interface/src/renderer/RenderUtil.cpp
+++ b/interface/src/renderer/RenderUtil.cpp
@@ -12,15 +12,15 @@
 #include "InterfaceConfig.h"
 #include "RenderUtil.h"
 
-void renderFullscreenQuad(float sMin, float sMax) {
+void renderFullscreenQuad(float sMin, float sMax, float tMin, float tMax) {
     glBegin(GL_QUADS);
-        glTexCoord2f(sMin, 0.0f);
+        glTexCoord2f(sMin, tMin);
         glVertex2f(-1.0f, -1.0f);
-        glTexCoord2f(sMax, 0.0f);
+        glTexCoord2f(sMax, tMin);
         glVertex2f(1.0f, -1.0f);
-        glTexCoord2f(sMax, 1.0f);
+        glTexCoord2f(sMax, tMax);
         glVertex2f(1.0f, 1.0f);
-        glTexCoord2f(sMin, 1.0f);
+        glTexCoord2f(sMin, tMax);
         glVertex2f(-1.0f, 1.0f);
     glEnd();
 }
diff --git a/interface/src/renderer/RenderUtil.h b/interface/src/renderer/RenderUtil.h
index 637596c78b..b2f244733a 100644
--- a/interface/src/renderer/RenderUtil.h
+++ b/interface/src/renderer/RenderUtil.h
@@ -12,7 +12,7 @@
 #ifndef hifi_RenderUtil_h
 #define hifi_RenderUtil_h
 
-/// Renders a quad from (-1, -1, 0) to (1, 1, 0) with texture coordinates from (sMin, 0) to (sMax, 1).
-void renderFullscreenQuad(float sMin = 0.0f, float sMax = 1.0f);
+/// Renders a quad from (-1, -1, 0) to (1, 1, 0) with texture coordinates from (sMin, tMin) to (sMax, tMax).
+void renderFullscreenQuad(float sMin = 0.0f, float sMax = 1.0f, float tMin = 0.0f, float tMax = 1.0f);
 
 #endif // hifi_RenderUtil_h