From c7a5223f1e2520ab13b480b937af1e208201de15 Mon Sep 17 00:00:00 2001
From: fgsfds <pvt.fgsfds@gmail.com>
Date: Sat, 7 Mar 2020 01:42:08 +0300
Subject: [PATCH] decouple repainting from blitting the FBO; draw touch overlay
 after FBO

---
 src/engine/e_graphics.pas  | 15 ++++++++++-----
 src/game/g_game.pas        | 13 +++++++++++++
 src/game/g_window.pas      |  9 ++++++++-
 src/game/sdl/g_system.pas  |  2 --
 src/game/sdl2/g_system.pas |  2 --
 5 files changed, 31 insertions(+), 10 deletions(-)

diff --git a/src/engine/e_graphics.pas b/src/engine/e_graphics.pas
index af999b1..5edceb2 100644
--- a/src/engine/e_graphics.pas
+++ b/src/engine/e_graphics.pas
@@ -64,6 +64,7 @@ procedure e_SetViewPort(X, Y, Width, Height: Word);
 procedure e_ResizeWindow(Width, Height: Integer);
 function e_ResizeFramebuffer(Width, Height: Integer): Boolean;
 procedure e_BlitFramebuffer(WinWidth, WinHeight: Integer);
+procedure e_SetRenderTarget(Framebuffer: Boolean);
 
 procedure e_Draw(ID: DWORD; X, Y: Integer; Alpha: Byte; AlphaChannel: Boolean;
                  Blending: Boolean; Mirror: TMirrorType = TMirrorType.None);
@@ -490,15 +491,22 @@ begin
   glTexCoord2f(u, v); glVertex2i(x1, y0);
 end;
 
+procedure e_SetRenderTarget(Framebuffer: Boolean);
+begin
+  if (e_FBO = 0) or e_NoGraphics then exit;
+  if Framebuffer then
+    glBindFramebuffer(GL_FRAMEBUFFER, e_FBO)
+  else
+    glBindFramebuffer(GL_FRAMEBUFFER, 0);
+end;
+
 procedure e_BlitFramebuffer(WinWidth, WinHeight: Integer);
 begin
   if (e_FBO = 0) or (e_Frame = 0) or e_NoGraphics then exit;
 
   glDisable(GL_BLEND);
   glEnable(GL_TEXTURE_2D);
-  glBindFramebuffer(GL_FRAMEBUFFER, 0);
   glBindTexture(GL_TEXTURE_2D, e_Frame);
-  e_SetViewPort(0, 0, WinWidth, WinHeight);
   glColor4ub(255, 255, 255, 255);
 
   glBegin(GL_QUADS);
@@ -507,9 +515,6 @@ begin
     glTexCoord2f(1, 0); glVertex2i(WinWidth, WinHeight);
     glTexCoord2f(1, 1); glVertex2i(WinWidth,         0);
   glEnd();
-
-  glBindFramebuffer(GL_FRAMEBUFFER, e_FBO);
-  e_SetViewPort(0, 0, e_FrameW, e_FrameH);
 end;
 
 procedure e_Draw(ID: DWORD; X, Y: Integer; Alpha: Byte; AlphaChannel: Boolean;
diff --git a/src/game/g_game.pas b/src/game/g_game.pas
index ca0bea8..e3d9b7b 100644
--- a/src/game/g_game.pas
+++ b/src/game/g_game.pas
@@ -3838,6 +3838,9 @@ begin
     FPSTime := Time;
   end;
 
+  e_SetRendertarget(True);
+  e_SetViewPort(0, 0, gScreenWidth, gScreenHeight);
+
   if gGameOn or (gState = STATE_FOLD) then
   begin
     if (gPlayer1 <> nil) and (gPlayer2 <> nil) then
@@ -4168,10 +4171,20 @@ begin
 
   if gGameOn then drawProfilers();
 
+  // TODO: draw this after the FBO and remap mouse click coordinates
+
 {$IFDEF ENABLE_HOLMES}
   g_Holmes_DrawUI();
 {$ENDIF}
 
+  // blit framebuffer to screen
+
+  e_SetRendertarget(False);
+  e_SetViewPort(0, 0, gWinSizeX, gWinSizeY);
+  e_BlitFramebuffer(gWinSizeX, gWinSizeY);
+
+  // draw the overlay stuff on top of it
+
   g_Touch_Draw;
 end;
 
diff --git a/src/game/g_window.pas b/src/game/g_window.pas
index 5d1c594..c4d1b0f 100644
--- a/src/game/g_window.pas
+++ b/src/game/g_window.pas
@@ -88,11 +88,18 @@ begin
 
     if forceUpdate then
     begin
+      e_SetRendertarget(True);
+      e_SetViewPort(0, 0, gScreenWidth, gScreenHeight);
+
       DrawMenuBackground('INTER');
       e_DarkenQuadWH(0, 0, gScreenWidth, gScreenHeight, 150);
-
       DrawLoadingStat();
       g_Console_Draw(True);
+
+      e_SetRendertarget(False);
+      e_SetViewPort(0, 0, gWinSizeX, gWinSizeY);
+      e_BlitFramebuffer(gWinSizeX, gWinSizeY);
+
       sys_Repaint;
       prevLoadingUpdateTime := getTimeMilli();
     end;
diff --git a/src/game/sdl/g_system.pas b/src/game/sdl/g_system.pas
index 68f9918..c53a7b3 100644
--- a/src/game/sdl/g_system.pas
+++ b/src/game/sdl/g_system.pas
@@ -173,8 +173,6 @@ implementation
 
   procedure sys_Repaint;
   begin
-    if glRenderToFBO then
-      e_BlitFramebuffer(gWinSizeX, gWinSizeY);
     SDL_GL_SwapBuffers
   end;
 
diff --git a/src/game/sdl2/g_system.pas b/src/game/sdl2/g_system.pas
index 992d6dc..b37ae0b 100644
--- a/src/game/sdl2/g_system.pas
+++ b/src/game/sdl2/g_system.pas
@@ -247,8 +247,6 @@ implementation
 
   procedure sys_Repaint;
   begin
-    if glRenderToFBO then
-      e_BlitFramebuffer(gWinSizeX, gWinSizeY);
     SDL_GL_SwapWindow(window)
   end;
 
-- 
2.29.2