FIx the mirror rendering bugs by replacing the prvious technique by a simple true mirror during the final blit for both rear view mirror and full screen mirror, not working for HMD

interface/src/Application.cpp

@@ -893,14 +893,15 @@ void Application::paintGL() {
         
         {
             float ratio = ((float)QApplication::desktop()->windowHandle()->devicePixelRatio() * getRenderResolutionScale());
-            auto mirrorViewport = glm::ivec4(0, 0, _mirrorViewRect.width() * ratio, _mirrorViewRect.height() * ratio);
+            // Flip the src and destination rect horizontally to do the mirror
-            auto mirrorViewportDest = mirrorViewport;
+            auto mirrorRect = glm::ivec4(0, 0, _mirrorViewRect.width() * ratio, _mirrorViewRect.height() * ratio);
+            auto mirrorRectDest = glm::ivec4(mirrorRect.z, mirrorRect.y, mirrorRect.x, mirrorRect.w);
             
             auto selfieFbo = DependencyManager::get<FramebufferCache>()->getSelfieFramebuffer();
             gpu::Batch batch;
             batch.setFramebuffer(selfieFbo);
             batch.clearColorFramebuffer(gpu::Framebuffer::BUFFER_COLOR0, glm::vec4(0.0f, 0.0f, 0.0f, 0.0f));
-            batch.blit(primaryFbo, mirrorViewport, selfieFbo, mirrorViewportDest);
+            batch.blit(primaryFbo, mirrorRect, selfieFbo, mirrorRectDest);
             batch.setFramebuffer(nullptr);
             renderArgs._context->render(batch);
         }
@@ -991,8 +992,14 @@ void Application::paintGL() {
             auto geometryCache = DependencyManager::get<GeometryCache>();
             auto primaryFbo = DependencyManager::get<FramebufferCache>()->getPrimaryFramebufferDepthColor();
             gpu::Batch batch;
-            batch.blit(primaryFbo, glm::ivec4(0, 0, _renderResolution.x, _renderResolution.y),
+
-                nullptr, glm::ivec4(0, 0, _glWidget->getDeviceSize().width(), _glWidget->getDeviceSize().height()));
+            if (renderArgs._renderMode == RenderArgs::MIRROR_RENDER_MODE) {
+                batch.blit(primaryFbo, glm::ivec4(0, 0, _renderResolution.x, _renderResolution.y),
+                    nullptr, glm::ivec4(_glWidget->getDeviceSize().width(), 0, 0, _glWidget->getDeviceSize().height()));
+            } else {
+                batch.blit(primaryFbo, glm::ivec4(0, 0, _renderResolution.x, _renderResolution.y),
+                    nullptr, glm::ivec4(0, 0, _glWidget->getDeviceSize().width(), _glWidget->getDeviceSize().height()));
+            }
 
             batch.setFramebuffer(nullptr);
 

interface/src/ui/ApplicationOverlay.cpp

@@ -193,6 +193,7 @@ void ApplicationOverlay::renderRearView(RenderArgs* renderArgs) {
         glm::vec2 texCoordMinCorner(0.0f, 0.0f);
         glm::vec2 texCoordMaxCorner(viewport.width() * renderRatio / float(selfieTexture->getWidth()), viewport.height() * renderRatio / float(selfieTexture->getHeight()));
 
+
         geometryCache->useSimpleDrawPipeline(batch, true);
         batch.setResourceTexture(0, selfieTexture);
         geometryCache->renderQuad(batch, bottomLeft, topRight, texCoordMinCorner, texCoordMaxCorner, glm::vec4(1.0f, 1.0f, 1.0f, 1.0f)); 

libraries/gpu/src/gpu/Batch.h

@@ -106,7 +106,10 @@ public:
     void clearStencilFramebuffer(int stencil, bool enableScissor = false); // not a command, just a shortcut for clearFramebuffer, it touches only stencil target
     void clearDepthStencilFramebuffer(float depth, int stencil, bool enableScissor = false); // not a command, just a shortcut for clearFramebuffer, it touches depth and stencil target
 
-    void blit(const FramebufferPointer& src, const Vec4i& srcViewport, const FramebufferPointer& dst, const Vec4i& dstViewport);
+    // Blit src framebuffer to destination
+    // the srcRect and dstRect are the rect region in source and destination framebuffers expressed in pixel space
+    // with xy and zw the bounding corners of the rect region.
+    void blit(const FramebufferPointer& src, const Vec4i& srcRect, const FramebufferPointer& dst, const Vec4i& dstRect);
 
     // Query Section
     void beginQuery(const QueryPointer& query);

libraries/render-utils/src/DeferredLightingEffect.cpp

@@ -407,7 +407,7 @@ void DeferredLightingEffect::render(RenderArgs* args) {
     args->_viewFrustum->evalProjectionMatrix(projMat);
     args->_viewFrustum->evalViewTransform(viewMat);
     if (args->_renderMode == RenderArgs::MIRROR_RENDER_MODE) {
-        viewMat.postScale(glm::vec3(-1.0f, 1.0f, 1.0f));
+  //      viewMat.postScale(glm::vec3(-1.0f, 1.0f, 1.0f));
     }
     batch.setProjectionTransform(projMat);
     batch.setViewTransform(viewMat);

libraries/render-utils/src/Model.cpp

@@ -159,7 +159,7 @@ void Model::RenderPipelineLib::addRenderPipeline(Model::RenderKey key,
         RenderKey mirrorKey(key.getRaw() | RenderKey::IS_MIRROR);
         auto mirrorState = std::make_shared<gpu::State>(state->getValues());
 
-        mirrorState->setFrontFaceClockwise(true);
+       // mirrorState->setFrontFaceClockwise(true);
 
         // create a new RenderPipeline with the same shader side and the mirrorState
         auto mirrorPipeline = gpu::PipelinePointer(gpu::Pipeline::create(program, mirrorState));

libraries/render-utils/src/RenderDeferredTask.cpp

@@ -166,9 +166,7 @@ void DrawOpaqueDeferred::run(const SceneContextPointer& sceneContext, const Rend
     Transform viewMat;
     args->_viewFrustum->evalProjectionMatrix(projMat);
     args->_viewFrustum->evalViewTransform(viewMat);
-    if (args->_renderMode == RenderArgs::MIRROR_RENDER_MODE) {
+
-        viewMat.preScale(glm::vec3(-1.0f, 1.0f, 1.0f));
-    }
     batch.setProjectionTransform(projMat);
     batch.setViewTransform(viewMat);
 
@@ -197,9 +195,7 @@ void DrawTransparentDeferred::run(const SceneContextPointer& sceneContext, const
     Transform viewMat;
     args->_viewFrustum->evalProjectionMatrix(projMat);
     args->_viewFrustum->evalViewTransform(viewMat);
-    if (args->_renderMode == RenderArgs::MIRROR_RENDER_MODE) {
+
-        viewMat.postScale(glm::vec3(-1.0f, 1.0f, 1.0f));
-    }
     batch.setProjectionTransform(projMat);
     batch.setViewTransform(viewMat);
     
@@ -259,9 +255,7 @@ void DrawOverlay3D::run(const SceneContextPointer& sceneContext, const RenderCon
     Transform viewMat;
     args->_viewFrustum->evalProjectionMatrix(projMat);
     args->_viewFrustum->evalViewTransform(viewMat);
-    if (args->_renderMode == RenderArgs::MIRROR_RENDER_MODE) {
+
-        viewMat.postScale(glm::vec3(-1.0f, 1.0f, 1.0f));
-    }
     batch.setProjectionTransform(projMat);
     batch.setViewTransform(viewMat);
     batch.setViewportTransform(args->_viewport);

libraries/render/src/render/DrawStatus.cpp

@@ -133,7 +133,7 @@ void DrawStatus::run(const SceneContextPointer& sceneContext, const RenderContex
     args->_viewFrustum->evalProjectionMatrix(projMat);
     args->_viewFrustum->evalViewTransform(viewMat);
     if (args->_renderMode == RenderArgs::MIRROR_RENDER_MODE) {
-        viewMat.postScale(glm::vec3(-1.0f, 1.0f, 1.0f));
+    //    viewMat.postScale(glm::vec3(-1.0f, 1.0f, 1.0f));
     }
     batch.setProjectionTransform(projMat);
     batch.setViewTransform(viewMat);

libraries/render/src/render/DrawTask.cpp

@@ -265,7 +265,7 @@ void DrawBackground::run(const SceneContextPointer& sceneContext, const RenderCo
     args->_viewFrustum->evalProjectionMatrix(projMat);
     args->_viewFrustum->evalViewTransform(viewMat);
     if (args->_renderMode == RenderArgs::MIRROR_RENDER_MODE) {
-        viewMat.postScale(glm::vec3(-1.0f, 1.0f, 1.0f));
+ //       viewMat.postScale(glm::vec3(-1.0f, 1.0f, 1.0f));
     }
     batch.setProjectionTransform(projMat);
     batch.setViewTransform(viewMat);