gamnit :: CustomTexture :: defaultinit
# 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
end
lib/gamnit/textures.nit:130,1--215,3