digitalmars.D - strange with alias this and import
- aquaratixc (348/348) Jan 31 2020 I have two files.
- Steven Schveighoffer (9/11) Jan 31 2020 _image is protected, so you can only use the alias-this inside the type
- aquaratixc (3/14) Jan 31 2020 Thanks
- aquaratixc (8/19) Jan 31 2020 I have another question (offtopic): from first file I want to
I have two files.
First file:
```
module ppmformats;
private
{
template addProperty(T, string propertyName)
{
import std.string : format, toLower;
const char[] addProperty = format(
`
private %2$s %1$s;
void set%3$s(%2$s %1$s)
{
this.%1$s = %1$s;
}
%2$s get%3$s()
{
return %1$s;
}
`,
"_" ~ propertyName.toLower,
T.stringof,
propertyName
);
}
auto EnumValue(E)(E e)
if(is(E == enum))
{
import std.traits : OriginalType;
OriginalType!E tmp = e;
return tmp;
}
}
class RGBColor
{
mixin(addProperty!(int, "R"));
mixin(addProperty!(int, "G"));
mixin(addProperty!(int, "B"));
this(int R = 0, int G = 0, int B = 0)
{
this._r = R;
this._g = G;
this._b = B;
}
const float luminance709()
{
return (_r * 0.2126f + _g * 0.7152f + _b * 0.0722f);
}
const float luminance601()
{
return (_r * 0.3f + _g * 0.59f + _b * 0.11f);
}
alias luminance = luminance709;
override string toString()
{
import std.string : format;
return format("RGBColor(%d, %d, %d, I = %f)", _r, _g, _b,
this.luminance);
}
RGBColor opBinary(string op, T)(T rhs)
{
import std.algorithm : clamp;
import std.string : format;
return mixin(
format(`new RGBColor(
clamp(cast(int) (_r %1$s rhs), 0, 255),
clamp(cast(int) (_g %1$s rhs), 0, 255),
clamp(cast(int) (_b %1$s rhs), 0, 255)
)
`,
op
)
);
}
RGBColor opBinary(string op)(RGBColor rhs)
{
import std.algorithm : clamp;
import std.string : format;
return mixin(
format(`new RGBColor(
clamp(cast(int) (_r %1$s rhs.getR), 0, 255),
clamp(cast(int) (_g %1$s rhs.getG), 0, 255),
clamp(cast(int) (_b %1$s rhs.getB), 0, 255)
)
`,
op
)
);
}
}
class AnyMapImage
{
mixin(addProperty!(int, "Width"));
mixin(addProperty!(int, "Height"));
private
{
RGBColor[] _image;
import std.algorithm : clamp;
auto actualIndex(size_t i)
{
auto S = _width * _height;
return clamp(i, 0, S);
}
auto actualIndex(size_t i, size_t j)
{
auto W = cast(size_t) clamp(i, 0, _width - 1);
auto H = cast(size_t) clamp(j, 0, _height - 1);
auto S = _width * _height;
return clamp(W + H * _width, 0, S);
}
}
this(int width, int height, RGBColor color = new RGBColor(0, 0,
0))
{
this._width = width;
this._height = height;
foreach (x; 0.._width)
{
foreach (y; 0.._height)
{
_image ~= color;
}
}
}
RGBColor opIndexAssign(RGBColor color, size_t x, size_t y)
{
_image[actualIndex(x, y)] = color;
return color;
}
RGBColor opIndexAssign(RGBColor color, size_t x)
{
_image[actualIndex(x)] = color;
return color;
}
RGBColor opIndex(size_t x, size_t y)
{
return _image[actualIndex(x, y)];
}
RGBColor opIndex(size_t x)
{
return _image[actualIndex(x)];
}
override string toString()
{
string accumulator = "[";
foreach (x; 0.._width)
{
string tmp = "[";
foreach (y; 0.._height)
{
tmp ~= _image[actualIndex(x, y)].toString ~ ", ";
}
tmp = tmp[0..$-2] ~ "], ";
accumulator ~= tmp;
}
return accumulator[0..$-2] ~ "]";
}
alias width = getWidth;
alias height = getHeight;
}
enum AnyMapFormat : string
{
PBM_TEXT = "P1",
PBM_BINARY = "P4",
PGM_TEXT = "P2",
PGM_BINARY = "P5",
PPM_TEXT = "P3",
PPM_BINARY = "P6",
}
abstract class ImageFile
{
protected
{
AnyMapImage _image;
AnyMapFormat _header;
}
abstract void load(string filename);
abstract void save(string filename);
}
class P6Image : ImageFile
{
this(int width, int height, RGBColor color = new RGBColor(0, 0,
0))
{
_image = new AnyMapImage(width, height, color);
_header = AnyMapFormat.PPM_BINARY;
}
override void load(string filename)
{
import std.conv;
import std.stdio;
import std.string;
File file;
with (file)
{
open(filename, "r");
if (readln.strip == EnumValue(_header))
{
auto imageSize = readln.split;
auto width = imageSize[0].parse!int;
auto height = imageSize[1].parse!int;
_image = new AnyMapImage(width, height);
auto buffer = new ubyte[width * 3];
readln;
for (uint i = 0; i < height; i++)
{
file.rawRead!ubyte(buffer);
for (uint j = 0; j < width; j++)
{
_image[j, i] = new RGBColor(
buffer[j * 3],
buffer[j * 3 + 1],
buffer[j * 3 + 2]
);
}
}
}
}
}
override void save(string filename)
{
import std.conv;
import std.stdio;
import std.string;
File file;
with (file)
{
enum MAXIMAL_LUMINANCE = 255;
open(filename, "w");
writeln(EnumValue(_header));
writeln(_image.getWidth, " ", _image.getHeight);
writeln(MAXIMAL_LUMINANCE);
foreach (i; 0.._image.getHeight)
{
foreach (j; 0.._image.getWidth)
{
auto currentColor = _image[j, i];
file.write(
cast(char) currentColor.getR,
cast(char) currentColor.getG,
cast(char) currentColor.getB,
);
}
}
}
}
alias _image this;
}
auto medianFilter(P6Image source, int M = 3, int N = 3)
{
auto imageWidth = source.getWidth;
auto imageHeight = source.getHeight;
auto edgeM = M / 2;
auto edgeN = N / 2;
auto simg = new P6Image(imageWidth, imageHeight);
for (int i = edgeM; i < imageWidth - edgeM; i++)
{
for (int j = edgeN; j < imageHeight - edgeN; j++)
{
RGBColor[] window;
for (int w = 0; w < M; w++)
{
for (int h = 0; h < N; h++)
{
window ~= source[i + w - edgeM, j + h - edgeN];
}
}
import std.algorithm : sort;
import std.range : array;
auto sortedWindow = (sort!"a.luminance <
b.luminance"(window)).array;
simg[i, j] = sortedWindow[(M + N) / 2];
}
}
return simg;
}
//void main()
//{
// import std.stdio;
// import std.algorithm : clamp;
//
// auto img = new P6Image(0, 0);
// img.load(`Lenna.ppm`);
// (img[0, 0] * 0.5).writeln;
//
// foreach (x; 0..img.width)
// {
// foreach (y; 0..img.height)
// {
// auto c = img[x, y];
// img[x, y] = c * new RGBColor(150, 0, 0);
// }
// }
// img.save(`Lenna2.ppm`);
// img.load(`noise.ppm`);
// medianFilter(img, 5, 5).save(`antinoise.ppm`);
//}
```
and second:
```
import ppmformats;
void main()
{
import std.stdio;
import std.algorithm : clamp;
auto img = new P6Image(0, 0);
img.load(`Lenna.ppm`);
(img[0, 0] * 0.5).writeln;
foreach (x; 0..img.width)
{
foreach (y; 0..img.height)
{
auto c = img[x, y];
img[x, y] = c * new RGBColor(150, 0, 0);
}
}
img.save(`Lenna2.ppm`);
img.load(`noise.ppm`);
medianFilter(img, 5, 5).save(`antinoise.ppm`);
}
```
By compilation I have this message:
```
e.d(10): Error: no [] operator overload for type
ppmformats.P6Image
e.d(12): Error: no property width for type ppmformats.P6Image
Failed: ["/usr/bin/dmd", "-v", "-o-", "e.d", "-I."]
```
How to fix this ?
Jan 31 2020
On 1/31/20 3:55 PM, aquaratixc wrote:How to fix this ?_image is protected, so you can only use the alias-this inside the type itself, or its derivatives. If you want to expose access, but not allow rebinding, create a public accessor: final AnyMapImage image() { return _image; } alias image this; Now, your other module can see the symbol. -Steve
Jan 31 2020
aquaratixc <disconnectix gmail.com> On Friday, 31 January 2020 at 21:16:07 UTC, Steven Schveighoffer wrote:On 1/31/20 3:55 PM, aquaratixc wrote:ThanksHow to fix this ?_image is protected, so you can only use the alias-this inside the type itself, or its derivatives. If you want to expose access, but not allow rebinding, create a public accessor: final AnyMapImage image() { return _image; } alias image this; Now, your other module can see the symbol. -Steve
Jan 31 2020
On Friday, 31 January 2020 at 21:16:07 UTC, Steven Schveighoffer wrote:On 1/31/20 3:55 PM, aquaratixc wrote:I have another question (offtopic): from first file I want to create one-file _source_ library for dub (I need it for instant access for features of this lib on my smartphone), but I don't understand how point to dub (in sdl format) what this file is source library. Know you how to do this?How to fix this ?_image is protected, so you can only use the alias-this inside the type itself, or its derivatives. If you want to expose access, but not allow rebinding, create a public accessor: final AnyMapImage image() { return _image; } alias image this; Now, your other module can see the symbol. -Steve
Jan 31 2020