# See the License for the specific language governing permissions and
# limitations under the License.
-# Services to load textures, create subtextures and manage their life-cycle
+# Load textures, create subtextures and manage their life-cycle
module textures
import display
-# Abstract gamnit texture
+# Texture composed of pixels, loaded from the assets folder by default
+#
+# Most textures should be created with `App` (as attributes)
+# for the method `create_scene` to load them.
+#
+# ~~~
+# import gamnit::flat
+#
+# redef class App
+# # Create the texture object, it will be loaded automatically
+# var texture = new Texture("path/in/assets.png")
+#
+# redef fun create_scene()
+# do
+# # Let `create_scene` load the texture
+# super
+#
+# # Use the texture
+# var sprite = new Sprite(texture, new Point3d[Float](0.0, 0.0, 0.0))
+# app.sprites.add sprite
+# end
+# end
+# ~~~
+#
+# Otherwise, they can be loaded and error checked explicitly after `create_scene`.
+#
+# ~~~nitish
+# var texture = new Texture("path/in/assets.png")
+# texture.load
+# var error = texture.error
+# if error != null then print_error error
+# ~~~
+#
+# A texture may also be created programmatically, like `CheckerTexture`,
+# or derived from another texture, using `subtexture`.
+# Textures with actual pixel data (not `Subtexture`) are `RootTexture`.
+# Texture loaded from the assets folder may in the PNG or JPG formats.
abstract class Texture
# Prepare a texture located at `path` within the `assets` folder
new (path: Text) do return new TextureAsset(path.to_s)
- # Root texture of which `self` is derived
- fun root: GamnitRootTexture is abstract
+ # Root texture from which `self` is derived
+ fun root: RootTexture is abstract
# Width in pixels of this texture
var width = 0.0
fun gl_texture: Int do return root.gl_texture
# Prepare a subtexture from this texture, from the given pixel offsets
- fun subtexture(left, top, width, height: Numeric): GamnitSubtexture
+ fun subtexture(left, top, width, height: Numeric): Subtexture
do
- # Setup the subtexture
- var subtex = new GamnitSubtexture(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 2x2 pixels
+# Colorful small texture of 32x32 pixels by default
class CheckerTexture
- super GamnitRootTexture
+ super RootTexture
+
+ # Width and height in pixels, defaults to 32
+ var size = 32 is optional
redef fun load(force)
do
- var pixels = [0xFFu8, 0x00u8, 0x00u8,
- 0x00u8, 0xFFu8, 0x00u8,
- 0x00u8, 0x00u8, 0xFFu8,
- 0xFFu8, 0xFFu8, 0xFFu8]
+ if gl_texture != -1 then return
+ load_checker size
+ loaded = true
+ end
+end
- var cpixels = new CByteArray.from(pixels)
+# 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"
- width = 2.0
- height = 2.0
- load_from_pixels(cpixels.native_array, 2, 2, gl_RGB)
+ # 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
- cpixels.destroy
+ var offset = 4*(x + y*width.to_i)
+ for i in [0..4[ do cpixels[offset+i] = bytes[i]
+
+ 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 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
+
+ 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
-# Texture with its own pixels
-class GamnitRootTexture
+# Texture with its own pixel data
+class RootTexture
super Texture
redef fun root do return self
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)
- if width > max_texture_size or height > max_texture_size then
- error = new Error("Texture {self} width or height is over the GL_MAX_TEXTURE_SIZE of {max_texture_size}")
+ var max_texture_size = glGetIntegerv(gl_MAX_TEXTURE_SIZE, 0)
+ if width > max_texture_size then
+ error = new Error("Texture width larger than gl_MAX_TEXTURE_SIZE ({max_texture_size}) in {self} at {width}")
+ return
+ else if height > max_texture_size then
+ error = new Error("Texture height larger than gl_MAX_TEXTURE_SIZE ({max_texture_size}) in {self} at {height}")
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
- # Set whether this texture should be pixelated when drawn, otherwise it is interpolated
- fun pixelated=(pixelated: Bool)
+ private fun load_checker(size: Int)
do
- # TODO this service could be made available in `Texture` when using
- # the kind of texture wrapper of gles v2 or maybe 3
+ var cpixels = new CByteArray(3*size*size)
+
+ var i = 0
+ for x in [0..size[ do
+ var quadrant_x = if x < size/2 then 0 else 1
+ for y in [0..size[ do
+ var quadrant_y = if y < size/2 then 0 else 1
+ var color = if quadrant_x == quadrant_y then
+ [0u8, 0u8, 0u8, 255u8]
+ else [255u8, 255u8, 255u8, 255u8]
+
+ for j in [0..3[ do cpixels[i+j] = color[j]
+ i += 3
+ end
+ end
- glBindTexture(gl_TEXTURE_2D, gl_texture)
+ width = size.to_f
+ height = size.to_f
+ load_from_pixels(cpixels.native_array, size, size, gl_RGB)
- var param = if pixelated then gl_NEAREST else gl_LINEAR
- glTexParameteri(gl_TEXTURE_2D, gl_TEXTURE_MIN_FILTER, param)
- glTexParameteri(gl_TEXTURE_2D, gl_TEXTURE_MAG_FILTER, param)
+ cpixels.destroy
end
# Has this resource been deleted?
# Texture loaded from the assets folder
class TextureAsset
- super GamnitRootTexture
+ super RootTexture
# Path to this texture within the `assets` folder
var path: String
load_from_platform
+ # If no pixel data was loaded, load the pixel default texture
+ if gl_texture == -1 then load_checker 32
+
loaded = true
end
end
# Texture derived from another texture, does not own its pixels
-class GamnitSubtexture
+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 fun root do return parent.root
+
+ 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 RGB 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