Experimental (PoC): xBR/EPX brick filtering for the iso HD view

LIB386/H/SVGA/VIDEO.H

@@ -48,6 +48,12 @@ void HandleEventsVideo(const void *event);
 typedef void (*PrePresentFn)(U32 *frameBuffer, U32 pitch, U32 width, U32 height, const U8 *palette_rgb);
 void SetPrePresentCallback(PrePresentFn fn);
 
+/** Optional SCENE-level pre-present pass, called BEFORE the pre-present overlay
+ *  (so it sits under the console/touch overlays). Same signature. Used by the
+ *  experimental iso xBR brick compositor to overwrite brick pixels in the
+ *  finished frame with an RGB-filtered layer. */
+void SetScenePresentCallback(PrePresentFn fn);
+
 /** Optional overlay rendered after the main pre-present callback. Used by the
  *  touch virtual gamepad overlay on Android so it draws on top of the console
  *  overlay. Same signature as PrePresentFn. */

LIB386/SVGA/SDL.CPP

@@ -30,6 +30,7 @@ U32 TabOffPhysLine[ADELINE_MAX_Y_RES];
 SDL_Palette *sdlPalette = NULL;
 S32 screenLockCount = 0;
 bool frameDirty = false;
+static PrePresentFn s_scenePresent = NULL;
 static PrePresentFn s_prePresent = NULL;
 static PrePresentFn s_overlayPrePresent = NULL;
 static PresentTimingFn s_presentBegin = NULL;
@@ -237,6 +238,10 @@ void CopyVideoArea(void *dst, const void *src, const U32 tabOffDst[],
     }
 }
 
+void SetScenePresentCallback(PrePresentFn fn) {
+    s_scenePresent = fn;
+}
+
 void SetPrePresentCallback(PrePresentFn fn) {
     s_prePresent = fn;
 }
@@ -308,15 +313,17 @@ static void PresentFrame() {
         }
     }
 
-    if (s_prePresent || s_overlayPrePresent) {
-        /* Build the 256-entry RGB table once; both callbacks take the same. */
+    if (s_scenePresent || s_prePresent || s_overlayPrePresent) {
+        /* Build the 256-entry RGB table once; the callbacks take the same. */
         static U8 paletteRgb[256 * 3];
         for (int i = 0; i < 256; i++) {
             U32 c = paletteLUT[i];
             paletteRgb[i * 3 + 0] = (U8)(c >> 16);
             paletteRgb[i * 3 + 1] = (U8)(c >> 8);
             paletteRgb[i * 3 + 2] = (U8)(c);
         }
+        if (s_scenePresent) /* scene composite first, under the overlays */
+            s_scenePresent((U32 *)stagingPixels, stagingPitch, ModeResX, ModeResY, paletteRgb);
         if (s_prePresent)
             s_prePresent((U32 *)stagingPixels, stagingPitch, ModeResX, ModeResY, paletteRgb);
         if (s_overlayPrePresent)

SOURCES/CONSOLE/CONSOLE_CMD.CPP

@@ -296,6 +296,13 @@ static void cmd_iso(int argc, const char *argv[]) {
     } else if (argc >= 2 && !strcmp(argv[1], "reset")) {
         SetIsoScale(ISO_SCALE_ONE);
         changed = 1;
+    } else if (argc >= 3 && !strcmp(argv[1], "epx")) {
+        extern S32 BrickEpxOn; /* GRILLE.CPP: composed-background brick filter (2x) */
+        BrickEpxOn = (S32)strtol(argv[2], NULL, 0);
+        FirstTime = AFF_ALL_FLIP;
+        Console_Print("iso epx = %d (0 off, 1 EPX-blend, 2 xBR, 3 xBR SSAA; interior, zoom > 1)",
+                      (int)BrickEpxOn);
+        return;
     } else if (argc >= 2 && !strcmp(argv[1], "probe")) {
         /* Compare the per-brick screen delta from the model projector
            (LongProjectPointIso, world coords; 1 brick = SIZE_BRICK_XZ 512 / _Y 256)