From 83ce72db486d16f09f4ca722288aefaa28146087 Mon Sep 17 00:00:00 2001
From: Christoph Oelckers <coelckers@users.noreply.github.com>
Date: Sun, 6 Jan 2019 13:35:31 +0100
Subject: [PATCH] - check the shader timer only once per frame, not once per
 draw call.

---
 src/gl/renderer/gl_renderer.cpp    |  4 +++-
 src/gl/renderer/gl_renderstate.cpp | 14 ++++++++------
 src/gl/renderer/gl_renderstate.h   |  3 +++
 3 files changed, 14 insertions(+), 7 deletions(-)

diff --git a/src/gl/renderer/gl_renderer.cpp b/src/gl/renderer/gl_renderer.cpp
index 6d6f38287b..3857f5e4f6 100644
--- a/src/gl/renderer/gl_renderer.cpp
+++ b/src/gl/renderer/gl_renderer.cpp
@@ -254,7 +254,9 @@ sector_t *FGLRenderer::RenderView(player_t* player)
 		bool saved_niv = NoInterpolateView;
 		NoInterpolateView = false;
 		// prepare all camera textures that have been used in the last frame
-		level.canvasTextureInfo.UpdateAll([&](AActor *camera, FCanvasTexture *camtex, double fov)
+		auto Level = player->mo->__GetLevel();
+		gl_RenderState.CheckTimer(Level->ShaderStartTime);
+		Level->canvasTextureInfo.UpdateAll([&](AActor *camera, FCanvasTexture *camtex, double fov)
 		{
 			RenderTextureView(camtex, camera, fov);
 		});
diff --git a/src/gl/renderer/gl_renderstate.cpp b/src/gl/renderer/gl_renderstate.cpp
index 9af56aac8a..18657e7487 100644
--- a/src/gl/renderer/gl_renderstate.cpp
+++ b/src/gl/renderer/gl_renderstate.cpp
@@ -93,12 +93,6 @@ void FGLRenderState::Reset()
 
 bool FGLRenderState::ApplyShader()
 {
-	static uint64_t firstFrame = 0;
-	// if firstFrame is not yet initialized, initialize it to current time
-	// if we're going to overflow a float (after ~4.6 hours, or 24 bits), re-init to regain precision
-	if ((firstFrame == 0) || (screen->FrameTime - firstFrame >= 1<<24) || level.ShaderStartTime >= firstFrame)
-		firstFrame = screen->FrameTime;
-
 	static const float nulvec[] = { 0.f, 0.f, 0.f, 0.f };
 	if (mSpecialEffect > EFF_NONE)
 	{
@@ -595,4 +589,12 @@ bool FGLRenderState::SetDepthClamp(bool on)
 	return res;
 }
 
+void FGLRenderState::CheckTimer(uint64_t ShaderStartTime)
+{
+	// if firstFrame is not yet initialized, initialize it to current time
+	// if we're going to overflow a float (after ~4.6 hours, or 24 bits), re-init to regain precision
+	if ((firstFrame == 0) || (screen->FrameTime - firstFrame >= 1 << 24) || ShaderStartTime >= firstFrame)
+		firstFrame = screen->FrameTime;
+}
+
 }
diff --git a/src/gl/renderer/gl_renderstate.h b/src/gl/renderer/gl_renderstate.h
index f72b1a61ef..671a7e506e 100644
--- a/src/gl/renderer/gl_renderstate.h
+++ b/src/gl/renderer/gl_renderstate.h
@@ -50,6 +50,8 @@ enum EPassType
 
 class FGLRenderState : public FRenderState
 {
+	uint64_t firstFrame = 0;
+
 	uint8_t mLastDepthClamp : 1;
 
 	float mGlossiness, mSpecularLevel;
@@ -102,6 +104,7 @@ public:
 	void Apply();
 	void ApplyBuffers();
 	void ApplyBlendMode();
+	void CheckTimer(uint64_t ShaderStartTime);
 
 	void ResetVertexBuffer()
 	{