After performing transformations such as rotation of a bitmap about an arbitrary point, the scale is lost. Of course, this makes sense because the bitmap is rotated inside the same bounds.<\/p>\n
To get the real scale now, along with the most reliable degree of rotation, I had to follow this method. Hope it saves the rest of you a night or two.<\/p>\n
[code lang=”java”]
\nfloat[] v = new float[9];
\nmatrix.getValues(v);
\n\/\/ translation is simple
\nfloat tx = v[Matrix.MTRANS_X];
\nfloat ty = v[Matrix.MTRANS_Y];<\/p>\n
\/\/ calculate real scale
\nfloat scalex = values[Matrix.MSCALE_X];
\nfloat skewy = values[Matrix.MSKEW_Y];
\nfloat rScale = (float) Math.sqrt(scalex * scalex + skewy * skewy);<\/p>\n
\/\/ calculate the degree of rotation
\nfloat rAngle = Math.round(Math.atan2(v[Matrix.MSKEW_X], v[Matrix.MSCALE_X]) * (180 \/ Math.PI));
\n[\/code]<\/p>\n","protected":false},"excerpt":{"rendered":"
After performing transformations such as rotation of a bitmap about an arbitrary point, the scale is lost. Of course, this makes sense because the bitmap is rotated inside the same bounds. To get the real scale now, along with the most reliable degree of rotation, I had to follow this method. Hope it saves the […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"jetpack_post_was_ever_published":false,"_jetpack_newsletter_access":"","_jetpack_dont_email_post_to_subs":false,"_jetpack_newsletter_tier_id":0,"_jetpack_memberships_contains_paywalled_content":false,"_jetpack_memberships_contains_paid_content":false,"footnotes":"","jetpack_publicize_message":"","jetpack_publicize_feature_enabled":true,"jetpack_social_post_already_shared":false,"jetpack_social_options":{"image_generator_settings":{"template":"highway","default_image_id":0,"font":"","enabled":false},"version":2}},"categories":[401,52],"tags":[556,454,448,455,451,444,450,440,449,438,452,453],"class_list":["post-1427","post","type-post","status-publish","format-standard","hentry","category-android","category-code","tag-android","tag-angle-of-rotation","tag-degree","tag-degree-of-rotation","tag-factor","tag-matrix","tag-real","tag-rotate","tag-rotation","tag-scale","tag-skew","tag-transformation"],"aioseo_notices":[],"jetpack_publicize_connections":[],"jetpack_featured_media_url":"","jetpack_shortlink":"https:\/\/wp.me\/pqtyx-n1","jetpack-related-posts":[{"id":1713,"url":"https:\/\/judepereira.com\/blog\/a-letter-to-tim-cook-regarding-ios-10-with-love-for-apple\/","url_meta":{"origin":1427,"position":0},"title":"A letter to Tim Cook regarding iOS 10, with love for Apple","author":"Jude Pereira","date":"June 17, 2016","format":false,"excerpt":"Tim, iOS has always been known for it's user interface, until recently. 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