examples/demo/04-bytepusher: Remove render target.

This doesn't need a render target to function. The comment suggested it was
needed to make debug text look better when scaled, but maybe logical
presentation used to do linear scaling exclusively at the time?

(cherry picked from commit 800f347e5e33b5f11b73a9a5f0a2afd8ebaf030f)

examples/demo/04-bytepusher/bytepusher.c

@@ -33,7 +33,6 @@ typedef struct {
     SDL_Renderer* renderer;
     SDL_Palette* palette;
     SDL_Texture* texture;
-    SDL_Texture* rendertarget; /* we need this render target for text to look good */
     SDL_AudioStream* audiostream;
     char status[SCREEN_W / 8];
     int status_ticks;
@@ -199,13 +198,11 @@ SDL_AppResult SDL_AppInit(void** appstate, int argc, char* argv[]) {
     }
 
     vm->texture = SDL_CreateTexture(vm->renderer, SDL_PIXELFORMAT_INDEX8, SDL_TEXTUREACCESS_STREAMING, SCREEN_W, SCREEN_H);
-    vm->rendertarget = SDL_CreateTexture(vm->renderer, SDL_PIXELFORMAT_UNKNOWN, SDL_TEXTUREACCESS_TARGET, SCREEN_W, SCREEN_H);
-    if (!vm->texture || !vm->rendertarget) {
+    if (!vm->texture) {
         return SDL_APP_FAILURE;
     }
     SDL_SetTexturePalette(vm->texture, vm->palette);
     SDL_SetTextureScaleMode(vm->texture, SDL_SCALEMODE_NEAREST);
-    SDL_SetTextureScaleMode(vm->rendertarget, SDL_SCALEMODE_NEAREST);
 
     if (!(vm->audiostream = SDL_OpenAudioDeviceStream(
         SDL_AUDIO_DEVICE_DEFAULT_PLAYBACK, &audiospec, NULL, NULL
@@ -274,26 +271,26 @@ SDL_AppResult SDL_AppIterate(void* appstate) {
     if (updated) {
         const void *pixels = &vm->ram[(Uint32)vm->ram[IO_SCREEN_PAGE] << 16];
         SDL_UpdateTexture(vm->texture, NULL, pixels, SCREEN_W);
+    }
 
-        SDL_SetRenderTarget(vm->renderer, vm->rendertarget);
-        SDL_RenderTexture(vm->renderer, vm->texture, NULL, NULL);
+    SDL_RenderClear(vm->renderer);
 
-        if (vm->display_help) {
-            print(vm, 4, 4, "Drop a BytePusher file in this");
-            print(vm, 8, 12, "window to load and run it!");
-            print(vm, 4, 28, "Press ENTER to switch between");
-            print(vm, 8, 36, "positional and symbolic input.");
-        }
+    if (vm->display_help) {
+        print(vm, 4, 4, "Drop a BytePusher file in this");
+        print(vm, 8, 12, "window to load and run it!");
+        print(vm, 4, 28, "Press ENTER to switch between");
+        print(vm, 8, 36, "positional and symbolic input.");
+    } else {
+        SDL_RenderTexture(vm->renderer, vm->texture, NULL, NULL);
+    }
 
-        if (vm->status_ticks > 0) {
-            vm->status_ticks -= 1;
-            print(vm, 4, SCREEN_H - 12, vm->status);
+    if (vm->status_ticks > 0) {
+        if (updated) {
+            vm->status_ticks--;
         }
+        print(vm, 4, SCREEN_H - 12, vm->status);
     }
 
-    SDL_SetRenderTarget(vm->renderer, NULL);
-    SDL_RenderClear(vm->renderer);
-    SDL_RenderTexture(vm->renderer, vm->rendertarget, NULL, NULL);
     SDL_RenderPresent(vm->renderer);
 
     return SDL_APP_CONTINUE;
@@ -387,7 +384,6 @@ void SDL_AppQuit(void* appstate, SDL_AppResult result) {
     if (appstate) {
         BytePusher* vm = (BytePusher*)appstate;
         SDL_DestroyAudioStream(vm->audiostream);
-        SDL_DestroyTexture(vm->rendertarget);
         SDL_DestroyTexture(vm->texture);
         SDL_DestroyPalette(vm->palette);
         SDL_DestroyRenderer(vm->renderer);