add background to god

src/buddies.cr

@@ -17,6 +17,8 @@ module Funfriend
 
     # Returns the textures this buddy uses
     abstract def textures : TextureMan::TextureBasket
+    # Texture to stretch over the whole canvas
+    abstract def bg_texture : Texture?
 
     # Implements the logic for the talk SFX, similar to corru.observer's `talk: () => ...`
     abstract def talk_sound
@@ -58,6 +60,10 @@ module Funfriend
       )
     end
 
+    def bg_texture : Texture?
+      nil
+    end
+
     def talk_sound
       SoundMan.play_sound("assets/sfx/talk#{(1..8).sample}.ogg")
     end
@@ -95,6 +101,10 @@ module Funfriend
       )
     end
 
+    def bg_texture : Texture?
+      TextureMan.load_texture("assets/buddies/god_bg.png")[:tex]
+    end
+
     def talk_sound
       SoundMan.play_sound("assets/sfx/talk_god#{(1..8).sample}.ogg")
     end

src/buddy_renderer.cr

@@ -1,15 +1,18 @@
 class Funfriend::BuddyRenderer
   getter buddy : Buddy
 
-  getter shader_program : Program
+  getter buddy_shader : Program
+  getter bg_shader : Program
   getter vertex_array : VertexArray
   getter vertex_buffer : Buffer
   getter textures : TextureMan::TextureBasket
+  getter bg_texture : Texture?
 
   def initialize(@buddy : Buddy)
-    @shader_program = init_shaders
+    @buddy_shader, @bg_shader = init_shaders
     @vertex_array, @vertex_buffer = init_buffers
     @textures = buddy.textures
+    @bg_texture = buddy.bg_texture
   end
 
   def funfriend_size
@@ -59,14 +62,7 @@ class Funfriend::BuddyRenderer
   end
 
   def init_shaders
-    vertex_shader_source = FileStorage.get("nop.vert").gets_to_end
-    fragment_shader_source = FileStorage.get("funfriend.frag").gets_to_end
-
-    vertex_shader = VertexShader.create(vertex_shader_source)
-    fragment_shader = FragmentShader.create(fragment_shader_source)
-
-    shaders = {vertex_shader, fragment_shader}
-    return Program.create(shaders)
+    {GL.shader("funfriend.frag", "nop.vert"), GL.shader("nop.frag", "nop.vert")}
   end
 
   def render(dt : Float64, window_width : Int32, window_height : Int32)
@@ -78,9 +74,23 @@ class Funfriend::BuddyRenderer
 
     width, height = frame[:width], frame[:height]
 
-    Texture::Unit.activate(0)
+    LibGL.enable(LibGL::BLEND)
+    LibGL.blend_func(LibGL::SRC_ALPHA, LibGL::ONE_MINUS_SRC_ALPHA)
+
+    if bg_texture
+      bg_texture.not_nil!.bind(Texture::Target::Texture2D) do
+        bg_shader.use do |shader|
+          shader.set_uniform("texture1", 0)
+
+          vertex_array.bind do
+            LibGL.draw_elements(LibGL::TRIANGLES, 6, DataType::UnsignedInt, Pointer(Void).new(0))
+          end
+        end
+      end
+    end
+
     frame[:tex].bind(Texture::Target::Texture2D) do
-      shader_program.use do |shader|
+      buddy_shader.use do |shader|
         shader.set_uniform("texture1", 0)
         shader.set_uniform("funfriendSize", funfriend_size[:width].to_f32, funfriend_size[:height].to_f32)
         shader.set_uniform("resolution", window_width.to_f32, window_height.to_f32)

src/gl.cr

@@ -12,4 +12,15 @@ module Funfriend::GL
       offset += size
     end
   end
+
+  def shader(fragment_filename : String, vertex_filename : String) : Program
+    vertex_shader_source = FileStorage.get(vertex_filename).gets_to_end
+    fragment_shader_source = FileStorage.get(fragment_filename).gets_to_end
+
+    vertex_shader = VertexShader.create(vertex_shader_source)
+    fragment_shader = FragmentShader.create(fragment_shader_source)
+
+    shaders = {vertex_shader, fragment_shader}
+    Program.create(shaders)
+  end
 end

src/text_renderer.cr

@@ -35,17 +35,13 @@ class Funfriend::TextRenderer
   end
 
   def init_shaders
-    vertex_shader_source = FileStorage.get("nop.vert").gets_to_end
-    fragment_shader_source = FileStorage.get("bake_alpha.frag").gets_to_end
-
-    vertex_shader = VertexShader.create(vertex_shader_source)
-    fragment_shader = FragmentShader.create(fragment_shader_source)
-
-    shaders = {vertex_shader, fragment_shader}
-    return Program.create(shaders)
+    GL.shader("nop.frag", "nop.vert")
   end
 
   def render(dt : Float64)
+    LibGL.enable(LibGL::BLEND)
+    LibGL.blend_func(LibGL::SRC_ALPHA, LibGL::ONE_MINUS_SRC_ALPHA)
+
     font_texture.bind(Texture::Target::Texture2D) do
       shader_program.use do |p|
         p.set_uniform("texture1", 0)