DEADSOFTWARE

decouple repainting from blitting the FBO; draw touch overlay after FBO
[d2df-sdl.git] / src / engine / e_graphics.pas
index 6e8966eaf5628467df56d3dc145d29f22f05193b..5edceb2c5f9d3c754a4d2f2f8e969fcd46410849 100644 (file)
@@ -62,6 +62,9 @@ type
 procedure e_InitGL();
 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);
@@ -151,6 +154,7 @@ var
   e_NoGraphics: Boolean = False;
   e_FastScreenshots: Boolean = true; // it's REALLY SLOW with `false`
   g_dbg_scale: Single = 1.0;
+  r_pixel_scale: Single = 1.0;
 
 
 implementation
@@ -196,6 +200,12 @@ var
   e_TextureFonts: array of TTextureFont = nil;
   e_CharFonts: array of TCharFont;
   //e_SavedTextures: array of TSavedTexture;
+  e_FBO: GLuint = 0;
+  e_RBO: GLuint = 0;
+  e_RBOSupported: Boolean = True;
+  e_Frame: GLuint = 0;
+  e_FrameW: Integer = -1;
+  e_FrameH: Integer = -1;
 
 //function e_getTextGLId (ID: DWORD): GLuint; begin result := e_Textures[ID].tx.id; end;
 
@@ -371,6 +381,94 @@ begin
  if Height <> nil then Height^ := e_Textures[ID].tx.Height;
 end;
 
+procedure DestroyFramebuffer;
+begin
+  glBindTexture(GL_TEXTURE_2D, 0);
+  glBindRenderbuffer(GL_RENDERBUFFER, 0);
+  glBindFramebuffer(GL_FRAMEBUFFER, 0);
+
+  if e_Frame > 0 then
+  begin
+    glDeleteTextures(1, @e_Frame);
+    e_Frame := 0;
+  end;
+
+  if e_RBO > 0 then
+  begin
+    glDeleteRenderbuffers(1, @e_RBO);
+    e_RBO := 0;
+  end;
+
+  if e_FBO > 0 then
+  begin
+    glDeleteFramebuffers(1, @e_FBO);
+    e_FBO := 0;
+  end;
+end;
+
+function e_ResizeFramebuffer(Width, Height: Integer): Boolean;
+begin
+  Result := False;
+
+  if e_NoGraphics then Exit;
+
+  DestroyFramebuffer;
+
+  e_FrameW := Width;
+  e_FrameH := Height;
+
+  glGetError();
+
+  glGenFramebuffers(1, @e_FBO);
+
+  if glGetError() <> GL_NO_ERROR then
+  begin
+    e_LogWriteln('GL: glGenFramebuffers failed');
+    Exit;
+  end;
+
+  glGenTextures(1, @e_Frame);
+  glBindTexture(GL_TEXTURE_2D, e_Frame);
+  glTexImage2D(GL_TEXTURE_2D, 0, GL_RGB, Width, Height, 0, GL_RGB, GL_UNSIGNED_BYTE, nil);
+  glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
+  glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
+
+  if glGetError() <> GL_NO_ERROR then
+  begin
+    e_LogWriteln('GL: can''t create FBO color buffer');
+    DestroyFramebuffer;
+    Exit;
+  end;
+
+  glBindFramebuffer(GL_FRAMEBUFFER, e_FBO);
+  glFramebufferTexture2D(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_TEXTURE_2D, e_Frame, 0);
+  if glCheckFramebufferStatus(GL_FRAMEBUFFER) <> GL_FRAMEBUFFER_COMPLETE then
+  begin
+    e_LogWriteln('GL: can''t construct framebuffer with color attachment');
+    DestroyFramebuffer;
+    Exit;
+  end;
+
+{$IFNDEF USE_GLES1}
+  if e_RBOSupported then
+  begin
+    glGenRenderbuffers(1, @e_RBO);
+    glBindRenderbuffer(GL_RENDERBUFFER, e_RBO);
+    glRenderbufferStorage(GL_RENDERBUFFER, GL_DEPTH24_STENCIL8, Width, Height);
+    glFramebufferRenderbuffer(GL_FRAMEBUFFER, GL_DEPTH_STENCIL_ATTACHMENT, GL_RENDERBUFFER, e_RBO);
+    if glCheckFramebufferStatus(GL_FRAMEBUFFER) <> GL_FRAMEBUFFER_COMPLETE then
+    begin
+      e_LogWriteln('GL: can''t construct framebuffer with depth+stencil attachment, trying without');
+      e_RBOSupported := False;
+      Result := e_ResizeFramebuffer(Width, Height);
+      Exit;
+    end;
+  end;
+{$ENDIF}
+
+  Result := True;
+end;
+
 procedure e_ResizeWindow(Width, Height: Integer);
 begin
   if Height = 0 then
@@ -387,18 +485,38 @@ begin
   y1 := y0+h;
        if Mirror = TMirrorType.Horizontal then begin tmp := x1; x1 := x0; x0 := tmp; end
   else if Mirror = TMirrorType.Vertical then begin tmp := y1; y1 := y0; y0 := tmp; end;
-  //HACK: make texture one pixel shorter, so it won't wrap
-  if (g_dbg_scale <> 1.0) then
-  begin
-    u := u*tw/(tw+1);
-    v := v*th/(th+1);
-  end;
   glTexCoord2f(0, v); glVertex2i(x0, y0);
   glTexCoord2f(0, 0); glVertex2i(x0, y1);
   glTexCoord2f(u, 0); glVertex2i(x1, y1);
   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);
+  glBindTexture(GL_TEXTURE_2D, e_Frame);
+  glColor4ub(255, 255, 255, 255);
+
+  glBegin(GL_QUADS);
+    glTexCoord2f(0, 1); glVertex2i(       0,         0);
+    glTexCoord2f(0, 0); glVertex2i(       0, WinHeight);
+    glTexCoord2f(1, 0); glVertex2i(WinWidth, WinHeight);
+    glTexCoord2f(1, 1); glVertex2i(WinWidth,         0);
+  glEnd();
+end;
+
 procedure e_Draw(ID: DWORD; X, Y: Integer; Alpha: Byte; AlphaChannel: Boolean;
                  Blending: Boolean; Mirror: TMirrorType = TMirrorType.None);
 begin
@@ -924,17 +1042,12 @@ begin
   else
     glDisable(GL_BLEND);
 
-  if Blending = TBlending.Blend then
-    glBlendFunc(GL_SRC_ALPHA, GL_ONE)
-  else
-    if Blending = TBlending.Filter then
-      glBlendFunc(GL_DST_COLOR, GL_SRC_COLOR)
-    else
-      if Blending = TBlending.Invert then
-        glBlendFunc(GL_ONE_MINUS_DST_COLOR, GL_ZERO)
-      else
-        if Alpha > 0 then
-          glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
+  case Blending of
+    TBlending.None: if Alpha > 0 then glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
+    TBlending.Blend: glBlendFunc(GL_SRC_ALPHA, GL_ONE);
+    TBlending.Invert: glBlendFunc(GL_ONE_MINUS_DST_COLOR, GL_ZERO);
+    TBlending.Filter: glBlendFunc(GL_ZERO, GL_SRC_COLOR);
+  end;
 
   glDisable(GL_TEXTURE_2D);
   glColor4ub(Red, Green, Blue, 255-Alpha);
@@ -950,7 +1063,6 @@ begin
   glEnd();
 
   glColor4ub(e_Colors.R, e_Colors.G, e_Colors.B, 255);
-
   glDisable(GL_BLEND);
 end;