Use RLE compression in tga_encoder
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@ -38,18 +38,31 @@ function image:encode_header()
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self.data = self.data
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.. string.char(0) -- image id
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.. string.char(0) -- color map type
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.. string.char(2) -- image type (uncompressed true-color image = 2)
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.. string.char(10) -- image type (RLE RGB = 10)
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self:encode_colormap_spec() -- color map specification
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self:encode_image_spec() -- image specification
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end
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function image:encode_data()
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local current_pixel = ''
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local previous_pixel = ''
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local count = 1
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local encoded = ''
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local rle_packet = ''
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for _, row in ipairs(self.pixels) do
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for _, pixel in ipairs(row) do
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self.data = self.data
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.. string.char(pixel[3], pixel[2], pixel[1])
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current_pixel = string.char(pixel[3], pixel[2], pixel[1])
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if current_pixel ~= previous_pixel or count == 128 then
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encoded = encoded .. rle_packet
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count = 1
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previous_pixel = current_pixel
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else
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count = count + 1
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end
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rle_packet = string.char(128 + count - 1) .. current_pixel
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end
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end
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self.data = self.data .. encoded .. rle_packet
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end
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function image:encode_footer()
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