Game developers strive to maximize immersion and engagement, to emotionally involve the audience in their material. One technique used to increase engagement is the development of new technologies, such as Stereoscopic 3D. Stereoscopic 3D (S3D) creates the impression of depth (stereopsis) in at images by providing additional binocular depth cues, such as convergence and binocular disparity. In this thesis, we explore the effects that S3D has on the player experience in an attempt to uncover design methodologies that can help game developers develop more effective content. Three experiments were designed and conducted to examine the effects S3D has on player experience and game design: i) Engagement in Stereoscopic 3D Games, ii) S3D Depth- Axis Interaction for Video Games: Performance and Engagement, iii) Depth Representation and Player Performance with Depth-Axis Interactivity. We hypothesized that S3D technology would increase immersion and engagement, and new mechanics that exploit the depth axis would be effective. The results of these studies suggest that S3D does not increase user engagement, and is consistent with prior research that suggest the impact of S3D is dependent on the game. They also demonstrate that developers can design unique experiences in stereoscopic 3D, but there may be additional ways to represent depth. The results suggest developers need to adjust the difficulty of their game when including stereoscopic 3D, depending on the interactions of their game. It is our recommendation that developers continue to explore the affordances offered by stereoscopic 3D to create unique experiences, but its inclusion is dependent on their specific game.

Teve-se por objetivo investigar se o tempo de exposição das informações de profundidade afeta a comparação de tamanho de objetos pictóricos. Para isso, 120 participantes distribuídos aleatoriamente em 12 grupos julgaram qual de duas barras verticais, uma a teste e outra a padrão, era maior. Usando o método dos estímulos constantes, estas barras podiam ser apresentadas simultaneamente por 50ms, 100ms ou 200ms em quatro condições de fundo de tela: (1) sem textura, (2) com apenas a linha do horizonte, (3) com o horizonte e o gradiente de linhas de compressão, e (4) com o horizonte e o gradiente de linhas de perspectiva. A inclinação das curvas psicométricas, os pontos de igualdade subjetiva (PIS) e o erro relativo foram calculados. A análise dos erros relativos indicou uma diferença significativa entre o gradiente de perspectiva e outras duas condições (controle e horizonte). Embora os tempos de exposição não tenham apresentado diferenças significativas entre si, observou-se uma maior superestimação do tamanho com apresentações de 100ms nas condições com indícios de profundidade (perspectiva e compressão). A análise das inclinações das curvas psicométricas mostrou uma maior sensibilidade dos participantes para efetuarem as comparações sob um tempo de 200ms em relação ao de 50ms, independentemente do fundo de tela. Os erros relativos maiores para a condição com linhas de perspectiva confirmam evidências de que esta é uma informação de profundidade eficiente na modulação do tamanho percebido. Além disso, é possível que essa eficiência seja maximizada nas condições em que os estímulos são expostos em torno dos 100ms. / The aim of this study was to investigate the effects of the duration of pictorial depth cue exposures on perceived sizes of stimuli. For this, 120 volunteers distributed randomly in 12 groups compared two vertical bars, one the test and other the standard, in to order to report which one was bigger. Using the method of constant stimuli, these bars could be presented simultaneously for 50, 100 or 200ms in four background conditions: (1) without depth cues, (2) with only the horizon, (3) with the horizon and compression line gradient, and (4) with the horizon and perspective line gradient. The slope of the psychometric curves, the points of subjectivity equality (PSE) and relative errors were calculated. The analysis of relative errors indicated a significant difference among the perspective gradient and other two conditions (without texture and horizon). Although exposure time had not presented significant differences among them, it was observed size overestimation during the 100ms exposure in depth cues conditions (compression and perspective). The analysis of slopes psychometric function showed a greater sensibility in the participants who made comparisons with 200ms than the ones who made with 50ms, independently of depth cue background. Pronounced relative errors in comparisons with perspective gradient tend to agree with previous studies, which demonstrate higher influence of this cue in perceived size modulation. Besides, this efficiency seems to be maximized when stimuli exposure time was 100ms.

As humans, we have evolved to see in three dimensions. Our ancestors developed two eyes that only look forward, which allows the visual area that can perceive depth to be most of the field of view. A variety of sensors have been developed which can determine depth in the environment. They range from producing individual points of depth to the depth of everything in the environment. These sensors have become cheap and can now reliably produce accurate depth. Research is needed to determine how to present the proximity information to the people using the sensors. Touch, sound, and vision have all been used to provide depth information to the users. This research focuses on vision and compares methods of visually presenting proximity information to a user. The methods examined are stereovision and false color visual proximity mapping. False color mapping proved most effective while, surprisingly, stereovision was not helpful.

Teve-se por objetivo investigar se o tempo de exposição das informações de profundidade afeta a comparação de tamanho de objetos pictóricos. Para isso, 120 participantes distribuídos aleatoriamente em 12 grupos julgaram qual de duas barras verticais, uma a teste e outra a padrão, era maior. Usando o método dos estímulos constantes, estas barras podiam ser apresentadas simultaneamente por 50ms, 100ms ou 200ms em quatro condições de fundo de tela: (1) sem textura, (2) com apenas a linha do horizonte, (3) com o horizonte e o gradiente de linhas de compressão, e (4) com o horizonte e o gradiente de linhas de perspectiva. A inclinação das curvas psicométricas, os pontos de igualdade subjetiva (PIS) e o erro relativo foram calculados. A análise dos erros relativos indicou uma diferença significativa entre o gradiente de perspectiva e outras duas condições (controle e horizonte). Embora os tempos de exposição não tenham apresentado diferenças significativas entre si, observou-se uma maior superestimação do tamanho com apresentações de 100ms nas condições com indícios de profundidade (perspectiva e compressão). A análise das inclinações das curvas psicométricas mostrou uma maior sensibilidade dos participantes para efetuarem as comparações sob um tempo de 200ms em relação ao de 50ms, independentemente do fundo de tela. Os erros relativos maiores para a condição com linhas de perspectiva confirmam evidências de que esta é uma informação de profundidade eficiente na modulação do tamanho percebido. Além disso, é possível que essa eficiência seja maximizada nas condições em que os estímulos são expostos em torno dos 100ms. / The aim of this study was to investigate the effects of the duration of pictorial depth cue exposures on perceived sizes of stimuli. For this, 120 volunteers distributed randomly in 12 groups compared two vertical bars, one the test and other the standard, in to order to report which one was bigger. Using the method of constant stimuli, these bars could be presented simultaneously for 50, 100 or 200ms in four background conditions: (1) without depth cues, (2) with only the horizon, (3) with the horizon and compression line gradient, and (4) with the horizon and perspective line gradient. The slope of the psychometric curves, the points of subjectivity equality (PSE) and relative errors were calculated. The analysis of relative errors indicated a significant difference among the perspective gradient and other two conditions (without texture and horizon). Although exposure time had not presented significant differences among them, it was observed size overestimation during the 100ms exposure in depth cues conditions (compression and perspective). The analysis of slopes psychometric function showed a greater sensibility in the participants who made comparisons with 200ms than the ones who made with 50ms, independently of depth cue background. Pronounced relative errors in comparisons with perspective gradient tend to agree with previous studies, which demonstrate higher influence of this cue in perceived size modulation. Besides, this efficiency seems to be maximized when stimuli exposure time was 100ms.

Accurate and usable x-ray vision has long been a goal in augmented reality (AR) research and development. X-ray vision, or the ability to comprehend location and object information when such is viewed through an opaque barrier, would be imminently useful in a variety of contexts, including industrial, disaster reconnaissance, and tactical applications. In order for x-ray vision to be a useful tool for many of these applications, it would need to extend operators’ perceptual awareness of the task or environment. The effectiveness with which x-ray vision can do this is of significant research interest and is a determinant of its usefulness in an application context. In substance, then, it is crucial to evaluate the effectiveness of x-ray vision—how does information presented through x-ray vision compare to real-world information? This approach requires narrowing as x-ray vision suffers from inherent limitations, analogous to viewing an object through a window. In both cases, information is presented beyond the local context, exists past an apparently solid object, and is limited by certain conditions. Further, in both cases, the naturally suggestive use cases occur over action space distances. These distances range from 1.5 to 30 meters and represent the area in which observers might contemplate immediate visually directed actions. These actions, simple tasks with a visual antecedent, represent action potentials for x-ray vision; in effect, x-ray vision extends an operators’ awareness and ability to visualize these actions into a new context. Thus, this work seeks to answer the question “Can a real window be replaced with an AR window?” This evaluation focuses on perceived object location, investigated through a series of experiments using visually directed actions as experimental measures. This approach leverages established methodology to investigate this topic by experimentally analyzing each of several distinct variables on a continuum between real-world depth perception and fully realized x-ray vision. It was found that a real window could not be replaced with an AR window without some loss of depth perception acuity and accuracy. However, no significant difference was found between a target viewed through an opaque wall and a target viewed through a real window.

This bachelor project investigates how to design a virtual reality (VR) user experience test to analyze the effect that the vergence-accommodation conflict (VAC) has on a users ability to judge focus. Furthermore, we want to investigate how the amount of depth cues can affect a user's perception of this conflict in VR. A user experience test has been designed through an iterative process where the prototype has gone through smaller user tests between each iteration. We validate the design through testing a larger number of participants, where we gather subjective data through the use of the “Think Aloud Method” as well as data based on the user's interactions within the test environment. Analyzed results show that the absence of depth cues makes it significantly harder for users to judge depth and focus, and that the presence of an additional reference-object in many cases is enough to assist users with this issue. Furthermore, we notice better user performance at closer distances. The aim of this investigation is to provide more information surrounding the perception of VAC, as it is one of the few issues within the VR industry that prevents us from experiencing depth in virtual worlds in a more realistic way. / Detta kandidatarbete undersöker hur man kan designa ett test i virtuell verklighet (VR) kring användarens upplevelse för att analysera effekten som "Vergence-Accommodation Conflict” (VAC) har på användarens förmåga att bedöma fokus. Vidare vill vi också ta reda på hur mängden ledtrådar för djupseende kan påverka användarens upplevelse av denna konflikt i VR. Ett test för användarens upplevelse har designats genom en iterativ process där prototypen genomgått mindre tester mellan iterationerna. Designen valideras genom ett större användartest där vi samlar subjektiv data genom användning av “Think Aloud Method” samt data baserat på användarens interaktion i testmiljön. Analyserad data visar att frånvaron av ledtrådar för djup har en betydande påverkan på användarens förmåga att bedöma djup och fokus, samt att närvaron av ytterligare ett referensobjekt i många fall är tillräckligt för att hjälpa användaren med detta problem. Vidare har vi kunnat se en bättre prestationsförmåga hos användarna på närmare distanser. Syftet med denna undersökning är att tillföra mer information kring upplevelsen av VAC, då det är ett av de få problem inom VR-industrin som hindrar oss från att uppleva djup i virtuella världar på ett mer realistiskt sätt.

Le but de cette étude est de vérifier l'apport de la stéréoscopie dans le phénomène de la constance de forme. La méthode utilisée consiste à mesurer la performance de différents participants (temps de réponse et de taux d'erreurs) à une tâche de prospection visuelle. Quatre groupes de participants ont effectué la tâche. Le premier groupe a été exposé à une présentation stéréoscopique des stimuli, le deuxième groupe à une présentation des stimuli en stéréoscopie inversée (la disparité binoculaire était inversée), le troisième groupe à des stimuli comprenant une information de texture, mais sans stéréoscopie et le quatrième groupe à des stimuli bi-dimensionnels, sans texture. Une interaction entre les effets de rotation (points de vue familiers vs. points de vue non familiers) et le type d'information de profondeur disponible (stéréoscopie, stéréoscopie inversée, texture ou ombrage) a été mise en évidence, le coût de rotation étant plus faible au sein du groupe exposé à une présentation en stéréoscopie inversée. Ces résultats appuient l'implication de représentations tridimensionnelles dans le traitement de l'information visuelle. / This study was conducted to evaluate the contribution of stereopsis to the shape constancy phenomenon. Four groups of eight participants each were asked to perform a visual exploration task. The first group was exposed to a stereoscopic stimulation, the second group was exposed to a reversed stereoscopic stimulation, the third group was exposed to a monocular stimulation with textures and shadow and the fourth group was exposed to a monocular stimulation with shadow only. Response times and error rates were used to measure participant's performance. Results show an interaction between rotation effects (familiar viewpoints vs. non-familiar viewpoints) and available depth cues (stereopsis, reversed stereopsis, textures and shadow, shadow only). The rotation cost was smaller in the group exposed to a reversed stereoscopic stimulation. These results are congruent with the use of tridimensional representations underlying visual processing.

Le but de cette étude est de vérifier l'apport de la stéréoscopie dans le phénomène de la constance de forme. La méthode utilisée consiste à mesurer la performance de différents participants (temps de réponse et de taux d'erreurs) à une tâche de prospection visuelle. Quatre groupes de participants ont effectué la tâche. Le premier groupe a été exposé à une présentation stéréoscopique des stimuli, le deuxième groupe à une présentation des stimuli en stéréoscopie inversée (la disparité binoculaire était inversée), le troisième groupe à des stimuli comprenant une information de texture, mais sans stéréoscopie et le quatrième groupe à des stimuli bi-dimensionnels, sans texture. Une interaction entre les effets de rotation (points de vue familiers vs. points de vue non familiers) et le type d'information de profondeur disponible (stéréoscopie, stéréoscopie inversée, texture ou ombrage) a été mise en évidence, le coût de rotation étant plus faible au sein du groupe exposé à une présentation en stéréoscopie inversée. Ces résultats appuient l'implication de représentations tridimensionnelles dans le traitement de l'information visuelle. / This study was conducted to evaluate the contribution of stereopsis to the shape constancy phenomenon. Four groups of eight participants each were asked to perform a visual exploration task. The first group was exposed to a stereoscopic stimulation, the second group was exposed to a reversed stereoscopic stimulation, the third group was exposed to a monocular stimulation with textures and shadow and the fourth group was exposed to a monocular stimulation with shadow only. Response times and error rates were used to measure participant's performance. Results show an interaction between rotation effects (familiar viewpoints vs. non-familiar viewpoints) and available depth cues (stereopsis, reversed stereopsis, textures and shadow, shadow only). The rotation cost was smaller in the group exposed to a reversed stereoscopic stimulation. These results are congruent with the use of tridimensional representations underlying visual processing.

Trois expériences ont été menées dans le but de déterminer quels codes sous-tendant la représentation de l’organisation spatiale des composantes des formes complexes contribuent aux discriminations d’objets complexes. Les trois expériences ont utilisé une tâche d’appariement simultané d’objets complexes. Aux essais négatifs, les objets pouvaient avoir des différences catégorielles de configuration, des différences métriques de configuration, des différences métriques de configuration et du rôle des parties ou des différences du rôle des parties seulement. La distance angulaire 2D ou 3D entre les stimuli pouvait varier. À l’expérience 1, les stimuli étaient présentés avec stéréoscopie et avaient une surface avec un gradient de texture de haut contraste. L’expérience 2 constitue une réplication de l’expérience 1 hormis pour l’utilisation de stimuli dont le contraste était réduit. Le but de cette manipulation était de vérifier si les résultats de l’expérience 1 sont répliqués avec une tâche dont le niveau de difficulté est plus élevé. Les stimuli de la troisième expérience avaient une surface gris mat et étaient présentés sans stéréoscopie. Les trois expériences ont montré que des codes catégoriel et pertinent aux rôles des parties contribuent à la discrimination d’objets complexes. Toutefois, ces codes sont dépendants aux orientations 2D et 3D, et ce, peu importe la richesse de l’information de profondeur présente dans les stimuli. De plus, nos résultats démontrent une plus grande sensibilité aux différences catégorielles de configuration qu’aux différences métriques. Enfin, un code métrique contribue également aux discriminations. Toutefois, la contribution de ce code disparaît lorsque la quantité d’information de profondeur est réduite. / Tree experiments were conducted to determine which codes underlie the representation of the spatial organisation of the components of complex shapes. The tree experiments used a simultaneous matching task of complex objects. For the negative trials, the objects could have categorical differences of configuration, metric differences of configuration, metric difference along with differences in the role of parts, and differences in the role of parts only. The 2D or 3D angular distance between the stimuli could vary. In experiment 1, the stimuli were presented with stereopsis and had a surface with high contrast texture. Experiment 2 replicates the condition of experiment 1, except that the contrast of the stimuli was reduced. The goal of this manipulation was to verify if the results of experiment 1 were replicated if task difficulty is increased. In experiment 3, the stimuli were presented without stereopsis and without texture. The tree experiments showed that a categorical code, and a code relevant to the role of the parts contribute to the discrimination of complex objects and that these codes are dependent to 2D and 3D orientation, independently of depth cues. The results also show a greater sensitivity to categorical than to metric configuration differences. Finally, a metric code also contributes to complex shapes discrimination. However, the contribution of this code disappears when the quantity of depth cues is reduced.

Mémoire numérisé par la Division de la gestion de documents et des archives de l'Université de Montréal.