rotation

问题 I loaded an image and I want it to rotate around its center, while its scale is getting larger. I know how to rotate an image around its center originally, but it's hard for me to calculate the position if the scale is getting larger. I tried it, but the image just 'dances', not staying in the center. 回答1: Short answer: Store the center of the source image rectangle and update the center of the rotated and zoomed image rectangle after the rotation and zoom operation, by the stored center

问题 I have implemented the Scale gesture for the container. Also, I have added onHorizontalDragUpdate and onVerticalDragUpdate. But when I try to add both, I get an exception saying can't implement both with Scale gesture. Even for Pan gesture, it throws the same exception. Below is my code: import 'package:flutter/material.dart'; import 'package:vector_math/vector_math_64.dart' hide Colors; import 'dart: math' as math; class HomeScreen extends StatefulWidget { @override State<StatefulWidget>

问题 I have implemented the Scale gesture for the container. Also, I have added onHorizontalDragUpdate and onVerticalDragUpdate. But when I try to add both, I get an exception saying can't implement both with Scale gesture. Even for Pan gesture, it throws the same exception. Below is my code: import 'package:flutter/material.dart'; import 'package:vector_math/vector_math_64.dart' hide Colors; import 'dart: math' as math; class HomeScreen extends StatefulWidget { @override State<StatefulWidget>

问题 I've been working with Flutter rotation, new Matrix4.identity() ..rotateX(degrees * 3.1415927 / 180), but, the problem, I want it to be similar to the diagram below. can I achieve a 3D-like rotation on the x-axis with Flutter? even if there is a mapping from 3D to 2D or there are alternatives that would get the same result. thanks in advance. Example image in OpenCV: How to calculate perspective transform for OpenCV from rotation angles? 回答1: thanks to this discussion, and this repo, and

问题 I've been working with Flutter rotation, new Matrix4.identity() ..rotateX(degrees * 3.1415927 / 180), but, the problem, I want it to be similar to the diagram below. can I achieve a 3D-like rotation on the x-axis with Flutter? even if there is a mapping from 3D to 2D or there are alternatives that would get the same result. thanks in advance. Example image in OpenCV: How to calculate perspective transform for OpenCV from rotation angles? 回答1: thanks to this discussion, and this repo, and

问题 I've been working with Flutter rotation, new Matrix4.identity() ..rotateX(degrees * 3.1415927 / 180), but, the problem, I want it to be similar to the diagram below. can I achieve a 3D-like rotation on the x-axis with Flutter? even if there is a mapping from 3D to 2D or there are alternatives that would get the same result. thanks in advance. Example image in OpenCV: How to calculate perspective transform for OpenCV from rotation angles? 回答1: thanks to this discussion, and this repo, and

问题 I need to make the arms and hands rotate around the center of the hook, as shown in the image below without them separating or changing their shape (no changes in the angles between arms and hands just rotation at A), as in the image below: I tried rotating the arms but this made them separate and change form. You can check out my code below: let hookCategoryName = "hook" let leftArmCategoryName = "leftArm" let rightArmCategoryName = "rightArm" let leftHandCategoryName = "leftHand" let

问题 I need to make the arms and hands rotate around the center of the hook, as shown in the image below without them separating or changing their shape (no changes in the angles between arms and hands just rotation at A), as in the image below: I tried rotating the arms but this made them separate and change form. You can check out my code below: let hookCategoryName = "hook" let leftArmCategoryName = "leftArm" let rightArmCategoryName = "rightArm" let leftHandCategoryName = "leftHand" let

问题 I doing some 2D drawing in a SWT GUI. For that I have a GC Object. How can I draw rotatet text inside of an SWT Canvas? 回答1: This should do it: Transform tr = new Transform(display); tr.rotate(-90); gc.setTransform(tr); gc.drawText("Text", x, y); 来源： https://stackoverflow.com/questions/12618023/how-to-draw-rotated-text-inside-of-a-gc

问题 I want to rotate a cube on world axis by using tween.I am able to rotate the cube around world axis without using tween by using rotateAroundWorldAxis(cube[1], new THREE.Vector3(0,1,0),degreeToRadians(90)); but I want to happen this slowly so I want to use it with tween. I was using var start = {x:cube[1].rotation.x, y:cube[1].rotation.y, z:cube[1].rotation.z}; var end = {x:cube[1].rotation.x , y:cube[1].rotation.y+degreeToRadians(90) , z:cube[1].rotation.z}; var tween = new TWEEN.Tween(start