# Prepare a subtexture from this texture, from the given pixel offsets
fun subtexture(left, top, width, height: Numeric): Subtexture
do
- # Setup the subtexture
- var subtex = new Subtexture(root, self, left.to_f, top.to_f, width.to_f, height.to_f)
- return subtex
+ return new AbsoluteSubtexture(self, left.to_f, top.to_f, width.to_f, height.to_f)
end
# Offset of the left border on `root` from 0.0 to 1.0
# Offset of the bottom border on `root` from 0.0 to 1.0
fun offset_bottom: Float do return 1.0
+
+ # 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
for i in [0..4[ do cpixels[offset+i] = bytes[i]
end
+ # Overwrite all pixels with `color`
+ #
+ # 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: `not loaded`
+ fun fill(color: Array[Float])
+ do
+ assert not loaded else print_error "{class_name}::fill already loaded"
+
+ # 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 255u8
+
+ 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]
+ i += 4
+ end
+ end
+ end
+
redef fun load(force)
do
if loaded then return
end
end
-# Texture with its own pixels
+# Texture with its own pixel data
class RootTexture
super Texture
init do all_root_textures.add self
+ # Should the pixels RGB values be premultiplied by their alpha value at loading?
+ #
+ # All gamnit textures must have premultiplied alpha, it provides a better
+ # alpha blending, avoids artifacts and allows for additive blending.
+ #
+ # When at `true`, the default, pixels RGB values are premultiplied
+ # at loading. Set to `false` if pixels RGB values are already
+ # premultiplied in the source data.
+ #
+ # This value must be set before calling `load`.
+ var premultiply_alpha = true is writable
+
private fun load_from_pixels(pixels: Pointer, width, height: Int, format: GLPixelFormat)
do
var max_texture_size = glGetIntegerv(gl_MAX_TEXTURE_SIZE, 0)
return
end
+ # Premultiply alpha?
+ if premultiply_alpha and format == gl_RGBA then
+ pixels.premultiply_alpha(width, height)
+ end
+
glPixelStorei(gl_UNPACK_ALIGNEMENT, 1)
var tex = glGenTextures(1)[0]
gl_texture = tex
glHint(gl_GENERATE_MIPMAP_HINT, gl_NICEST)
glGenerateMipmap(gl_TEXTURE_2D)
+ glTexParameteri(gl_TEXTURE_2D, gl_TEXTURE_MIN_FILTER, gl_LINEAR_MIPMAP_LINEAR)
+
+ glBindTexture(gl_TEXTURE_2D, 0)
end
private fun load_checker(size: Int)
cpixels.destroy
end
- # Set whether this texture should be pixelated when drawn, otherwise it is interpolated
- fun pixelated=(pixelated: Bool)
- do
- # TODO this service could be made available in `Texture` when using
- # the kind of texture wrapper of gles v2 or maybe 3
-
- glBindTexture(gl_TEXTURE_2D, gl_texture)
-
- var param = if pixelated then gl_NEAREST else gl_LINEAR
- glTexParameteri(gl_TEXTURE_2D, gl_TEXTURE_MAG_FILTER, param)
- end
-
# Has this resource been deleted?
var deleted = false
end
# Texture derived from another texture, does not own its pixels
-class Subtexture
+abstract class Subtexture
super Texture
- redef var root
-
# Parent texture, from which this texture was created
var parent: Texture
- # Left border of this texture compared to `parent`
+ redef var root = parent.root is lateinit
+
+ redef fun load(force) do root.load(force)
+end
+
+# Subtexture created from pixel coordinates within `parent`
+class AbsoluteSubtexture
+ super Subtexture
+
+ # Left border of this texture relative to `parent`
var left: Float
- # Top border of this texture compared to `parent`
+ # Top border of this texture relative to `parent`
var top: Float
private fun set_wh(width, height: Float)
self.height = height
end
- redef fun load(force) do root.load(force)
-
redef var offset_left = parent.offset_left + left / root.width is lazy
redef var offset_top = parent.offset_top + top / root.height is lazy
redef var offset_right = offset_left + width / root.width is lazy
redef var offset_bottom = offset_top + height / root.height is lazy
end
+# Subtexture created from relative coordinates ([0..1]) out of the `root` texture
+class RelativeSubtexture
+ super Subtexture
+
+ redef var offset_left
+ redef var offset_top
+ redef var offset_right
+ redef var offset_bottom
+
+ redef fun width do return root.width * (offset_right - offset_left)
+ redef fun height do return root.height * (offset_bottom - offset_top)
+end
+
redef class Sys
# All declared root textures
var all_root_textures = new TextureSet
# Load all texture of this set
fun load_all do for t in self do t.load
end
+
+redef class Pointer
+ # Multiply RBG values by their alpha value
+ private fun premultiply_alpha(width, height: Int) `{
+ uint8_t *bytes = (uint8_t *)self;
+ int x, y, i = 0;
+ for(y = 0; y < height; y ++) {
+ for(x = 0; x < width; x ++) {
+ int a = bytes[i+3];
+ bytes[i ] = bytes[i ] * a / 255;
+ bytes[i+1] = bytes[i+1] * a / 255;
+ bytes[i+2] = bytes[i+2] * a / 255;
+ i += 4;
+ }
+ }
+ `}
+end
nitlanguage / nit.git / blobdiff