Exploring ‘Instancing’ and Its Applications in 3D Programming

‘Instancing’ is a technique widely used in 3D programming to draw multiple copies of an object with a single drawing command. The conventional approach of drawing several copies of an object is to send a separate drawing command for each copy. However, instancing facilitates drawing several copies of an object with repeating patterns substantially quicker than conventional approaches. With instancing, an object’s geometry data is stored once for drawing several copies of it. Without instancing, information is stored per copy requiring an additional amount of memory for each additional copy, so, an object’s geometry is read afresh each time it is drawn. Instancing makes better memory usage and faster execution of the program as it knows the geometry of an object before drawing multiple copies of it. Millions, or even billions of objects can be drawn in the blink of an eye because a Graphics Processing Unit (GPU) accelerates computation with its massively parallel architecture. Instancing is popular in film and animation for rendering forests, flower fields, crowd simulations, and more. This research explores different applications of instancing. While drawing multiple copies of the same object, different patterns or characteristics are also incorporated. For example, a tulip festival is generated from a single tulip plant by instantiating an assortment of colors in different rows. A floral park with varied patterns of plants, soldiers in a battlefield in different movements, and more have been explored

Shape Transformation of Multiple Objects Using Slices

3D shape transformation is usually confined to transformation between a pair of objects. The objective of this paper is to look at shape transformation from a different perspective: instead of binding this concept between two objects, the technique is extended to the concept of incorporating the characteristics of a number of objects in one body at a time. Equal number of slices are generated from all objects. Slices may be parallel to each other or each slice may have different orientation. Traversal of a data along its longitudinal direction may generate slices which are differently oriented from each other. When multiple objects are transformed to one and is used as an influence shape, it also works as incorporating multiple influence shapes at a time during transformation between two objects. The paper shows the ease of implementation of this concept in sliced data and also discusses its extendibility

3d Morphing And Shape Transformation Using Slices

Secara umum istilah ’Transformasi Rupa Bentuk’ bermaksud transformasi sebuah objek kepada sebuah objek yang lain. Apabila transformasi rupa bentuk melibatkan dua buah objek iaitu objek sumber dan objek destinasi, dan terdapat pelenyapan rupa bentuk objek sumber kepada objek destinasi secara beransur-ansur, berterusan dan serentak maka transformasi rupa bentuk ini dipanggil ’Pemorfan’. Kebanyakan algoritma transformasi rupa bentuk sedia ada melibatkan banyak campur tangan pengguna, tidak boleh diskalakan dengan rapi apabila bilangan objek input lebih daripada dua dan tidak boleh diskalakan dalam persekitaran perkomputeran selari dan teragih apabila diperlukan. Tesis ini menyentuh isu-isu tersebut dengan mencadangkan algoritma pemorfan 3D yang novel menggunakan hirisan. Pada mulanya objek sumber dan destinasi disusur, dan hirisan dijana daripada penyusuran berkenaan. Penyusuran data tertentu mungkin menjana hirisan yang tidak semestinya selari antara satu sama lain. Bilangan hirisan yang sama dijana bagi kedua-dua objek sumber dan destinasi. Sempadan kedua-dua objek berkenaan diekstrak. Sempadan berkenaan kemudiannya disusur pada satah 2D dan ditransformasikan kepada masing-masing satu awan titik kontur. Interpolasi awan titik kontur sumber dan destinasi yang sepadan dilakukan, dan permukaan yang ditransformasikan dibina semula. Generally the term ‘Shape Transformation’ means transformation of one object into another object. When shape transformation involves two objects i.e. source object and destination object and there is gradual, continuous and simultaneous dissolvement of the shape of source object to destination object, it is called ‘Morphing’. Most of the existing shape transformation algorithms involve a lot of user intervention, do not scale well when the number of input objects is more than two and are not scalable in parallel and distributed computing environment whenever needed. This thesis addresses the above-mentioned issues by proposing a novel 3D morphing algorithm using slices. Firstly source and destination objects are traversed and slices are generated from this traversal. Traversal of a particular data may generate slices which may not be parallel to each other. Equal number of slices is generated for both source and destination objects. Boundaries of both objects are extracted. The boundaries are then traversed on a 2D plane and are transformed into a cloud of contour points each. Interpolation of the corresponding source and destination contour point clouds takes place and transformed surface is reconstructed

A cyto-epidemiological study on married women in reproductive age group (15-49 years) regarding reproductive tract infection in a rural community of West Bengal

Background: Reproductive tract infection (RTI) represents a major public health problem in India. Women are either not aware of the symptoms of RTI or refuse to seek health care due to economic and time constrains unless suffering from alarming symptoms. Objectives: To find out the prevalence of women with suggestive symptoms of RTI; to identify clinical and cytological abnormalities among the symptomatic women and to find out association between socio-demographic profile and risk factors with RTI symptomatic and cytology positive patients. Materials and Methods: A total of 385 married women in reproductive age group residing in Baligori sub-center area in Tarakeswar block of Hooghly district, West Bengal, India, were screened for symptom suggestive of RTI; symptomatic women went through gynecological examination and cancer cervix screening by Pap smear. Analysis of results was done by Odds ratio and multivariate logistic regression. Results: Overall, 23.6% of the study population had symptoms suggestive of RTI. Most of them (68.1%) had abnormal vaginal discharge. Among the symptomatic women, cytology proved that 24.4% were suffering from acute cervicitis, 4.7% from A Squamous Cell of Undetermined Significance (ASCUS) and 2.3% from Low Grade Intra epithelial Lesion (LSIL) Squamous. Statistically significant association was observed for age, number of children, contact history of husband, pond bathing, menstrual hygiene, intra uterine device insertion, non-usage of barrier method, and history of abortion among women symptomatic for RTI and asymptomatic women. Conclusions: Prevalence of suggestive symptoms of RTI in women was found to be high (23.6%), and among them 7% had cervical dysplasia. Therefore, enhancing awareness and organizing screening camps are absolute necessity and must be held at frequent intervals to curb the menace due to cervical cancer

A new approach to virtual palpation

In this paper, a new approach to virtual medical abdominal palpation has been introduced. Firstly, we describe palpation as a medical procedure. Then, we analyze the necessity of virtual palpation. Next, we present our survey on the existing work on virtual palpation. Then, we propose a new image-driven function-based approach to virtual palpation to address the weakness of the previous works. Lastly, we discuss the advantages of our method over other existing works

Virtual palpation for medical training in cyberworlds

In this paper, we introduce a new approach to virtual palpation for medical training in cyber worlds. We analyze palpation as a medical procedure. Then, we survey the existing virtual palpation projects, which use haptic devices, and propose a new image-driven approach to haptic palpation that can be easily ported to any web-enabled and collaborative environments. We also introduce variable haptic interaction point that allows us to implement multiple-point haptic interaction while using a single-point desktop haptic device. Lastly, we prove our hypothesis by implementing the proposed approach for abdominal palpation and validating it with medical practitioners. We also discuss the advantages of our method over other existing works in terms of flexibility, simplicity and scalability

Haptic editing of MRI brain data

Automated brain segmentation may leave errors which can be identified by comparing the location of the actual MRI voxels with reference to the reconstructed pial polygonal surface of the brain. Location of the segmentation errors can be marked by displaying color spots on the brain surface followed by its interactive editing, as we previously proposed. In this paper, a new haptic friction-based approach of identifying and correcting errors has been discussed. The user can feel as different friction the discrepancy along the reconstructed surface by moving a haptic proxy along it followed by rubbing the surface as if it is being polished. The proposed approach does not only limit its application in editing of medical data, but can also be successfully used for visually impaired group as this dynamic friction-based editing helps any novice user identify error prone area just by touching the surface

Haptic editing of MRI brain data

Automated brain segmentation may leave errors which can be identified by comparing the location of the actual MRI voxels with reference to the reconstructed pial polygonal surface of the brain. Location of the segmentation errors can be marked by displaying color spots on the brain surface followed by its interactive editing, as we previously proposed. In this paper, a new haptic friction-based approach of identifying and correcting errors has been discussed. The user can feel as different friction the discrepancy along the reconstructed surface by moving a haptic proxy along it followed by rubbing the surface as if it is being polished. The proposed approach does not only limit its application in editing of medical data, but can also be successfully used for visually impaired group as this dynamic friction-based editing helps any novice user identify error prone area just by touching the surface