0b029011dd
currently the support is limited to images that can only report their sizes and pinholes and where equal? signals an error unless the arguments are eq?. original commit: a744958fd539471315b7515e3e9460af861aa7b7
37 lines
1.0 KiB
Racket
37 lines
1.0 KiB
Racket
#lang racket/base
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(require racket/class)
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(provide fetch image<%>
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get-shape set-shape get-bb get-pinhole
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get-normalized? set-normalized get-normalized-shape)
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(define-local-member-name
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get-shape set-shape get-bb get-pinhole
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get-normalized? set-normalized get-normalized-shape)
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(define image<%>
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(interface ()
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get-shape set-shape get-bb get-pinhole
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get-normalized? get-normalized-shape))
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(define (fetch bytes)
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(let* ([str
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(and bytes
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(with-handlers ((exn:fail? (λ (x) #f)))
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(bytes->string/utf-8 bytes)))]
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[lst (and str
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(with-handlers ((exn:fail:read? (λ (x) #f)))
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(racket/base:read
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(open-input-string
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str))))])
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(cond
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[(and (list? lst)
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(= 2 (length lst)))
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;; backwards compatibility for saved images that didn't have a pinhole
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(list (list-ref lst 0)
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(list-ref lst 1)
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#f)]
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[else
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lst])))
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(define racket/base:read read)
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