+
+ # Should this texture be drawn pixelated when magnified? otherwise it is interpolated
+ #
+ # This setting affects all the textures based on the same pixel data, or `root`.
+ #
+ # Must be set after a successful call to `load`.
+ fun pixelated=(pixelated: Bool)
+ do
+ if root.gl_texture == -1 then return
+
+ # TODO do not modify `root` by using *sampler objects* in glesv3
+ glBindTexture(gl_TEXTURE_2D, root.gl_texture)
+
+ var param = if pixelated then gl_NEAREST else gl_LINEAR
+ glTexParameteri(gl_TEXTURE_2D, gl_TEXTURE_MAG_FILTER, param)
+ end
+end
+
+# Colorful small texture of 32x32 pixels by default
+class CheckerTexture
+ super RootTexture
+
+ # Width and height in pixels, defaults to 32
+ var size = 32 is optional
+
+ redef fun load(force)
+ do
+ if gl_texture != -1 then return
+ load_checker size
+ loaded = true
+ end
+end
+
+# Custom texture with pixel values filled programmatically
+#
+# At creation, the texture is composed of `width` by `height` (rounded down)
+# transparent pixels. The pixels value can be set using `[]=`.
+#
+# ~~~
+# # Build a texture with 4 colors
+# var tex = new CustomTexture(2.0, 2.0)
+# tex[0, 0] = [1.0, 0.0, 0.0] # Red
+# tex[0, 1] = [0.0, 1.0, 0.0] # Green
+# tex[1, 0] = [0.0, 0.0, 1.0] # Blue
+# tex[1, 1] = [1.0, 1.0, 1.0, 0.5] # Transparent white
+# tex.load
+# ~~~
+class CustomTexture
+ super RootTexture
+
+ redef var width
+ redef var height
+
+ private var cpixels = new CByteArray(4*width.to_i*height.to_i) is lazy
+
+ # Set the `color` of the pixel at `x`, `y` (from the top-left corner)
+ #
+ # The argument `color` should be an array of up to 4 floats (RGBA).
+ # If `color` has less than 4 items, the missing items are replaced by 1.0.
+ #
+ # Require: `x < width.to_i and y < height.to_i`
+ fun []=(x, y: Int, color: Array[Float])
+ do
+ assert x < width.to_i and y < height.to_i else print_error "{class_name}::[] out of bounds"
+
+ # Simple conversion from [0.0..1.0] to [0..255]
+ var bytes = [for c in color do (c*255.0).round.to_i.clamp(0, 255).to_bytes.last]
+ while bytes.length < 4 do bytes.add 255
+
+ var offset = 4*(x + y*width.to_i)
+ for i in [0..4[ do cpixels[offset+i] = bytes[i].to_b
+
+ loaded = false
+ end
+
+ # Overwrite all pixels with `color`, return `self`
+ #
+ # The argument `color` should be an array of up to 4 floats (RGBA).
+ # If `color` has less than 4 items, the missing items are replaced by 1.0.
+ fun fill(color: Array[Float]): SELF
+ do
+ # Simple conversion from [0.0..1.0] to [0..255]
+ var bytes = [for c in color do (c*255.0).round.to_i.clamp(0, 255).to_bytes.last]
+ while bytes.length < 4 do bytes.add 255
+
+ var i = 0
+ for x in [0..width.to_i[ do
+ for y in [0..height.to_i[ do
+ for j in [0..4[ do cpixels[i+j] = bytes[j].to_b
+ i += 4
+ end
+ end
+
+ loaded = false
+ return self
+ end
+
+ redef fun load(force)
+ do
+ force = force or else false
+ if loaded and not force then return
+
+ if force and glIsTexture(gl_texture) then
+ # Was already loaded, free the previous GL name
+ glDeleteTextures([gl_texture])
+ end
+ gl_texture = -1
+
+ # Round down the desired dimension
+ var width = width.to_i
+ var height = height.to_i
+ self.width = width.to_f
+ self.height = height.to_f
+
+ load_from_pixels(cpixels.native_array, width, height, gl_RGBA)
+
+ loaded = true
+ end