shithub: choc

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Video: Use intended function sequence to update "streaming" texture

Regarding to the SDL wiki, SDL_UpdateTexture is a fairly slow function,
intended for use with static textures that do not change often.

--- a/src/i_video.c

+++ b/src/i_video.c

@@ -157,6 +157,8 @@

 static SDL_Surface *screenbuffer = NULL;

 static SDL_Surface *rgbabuffer = NULL;

 static SDL_Texture *texture = NULL;

+static int pitch;

+static void *pixels;

 // palette

@@ -1104,10 +1106,10 @@

     SDL_BlitSurface(screenbuffer, NULL, rgbabuffer, NULL);

     // Update the texture with the content of the 32-bit RGBA buffer

-    // (the last argument is the pitch, i.e. 320 pixels of 4 RGBA-bytes)

-    SDL_UpdateTexture(texture, NULL, rgbabuffer->pixels,

-                      SCREENWIDTH * sizeof(Uint32));

+    SDL_LockTexture(texture, NULL, &pixels, &pitch);

+    memcpy(pixels, rgbabuffer->pixels, SCREENHEIGHT*pitch);

+    SDL_UnlockTexture(texture);

     // Render the texture into the window