Fixed setting the texture unit, still doesn't work.

src/render/opengl/SDL_render_gl.c

@@ -282,7 +282,7 @@ GL_CreateRenderer(SDL_Window * window, Uint32 flags)
     }
 
     /* Check for shader support */
-    //data->shaders = GL_CreateShaderContext();
+    data->shaders = GL_CreateShaderContext();
 
 #if 0
     /* We support YV12 textures using 3 textures and a shader */

src/render/opengl/SDL_shaders_gl.c

@@ -183,7 +183,7 @@ CompileShaderProgram(GL_ShaderContext *ctx, int index, GL_ShaderData *data)
         SDL_snprintf(tex_name, SDL_arraysize(tex_name), "tex%d", i);
         location = ctx->glGetUniformLocationARB(data->program, tex_name);
         if (location >= 0) {
-            ctx->glUniform1iARB(location, 1);
+            ctx->glUniform1iARB(location, i);
         }
     }
     ctx->glUseProgramObjectARB(0);