Estendendo uma API Gráca com Materiais Programáveis

Abstract

In computer graphics, rasterization is one of the primary rendering methods, involving the projection of scene polygons onto the screen plane to calculate which pixels they cover. Control over the visual appearance of this process is granted to the developer through shaders, programs executed directly on the GPU. One of these shaders is the fragment shader, or pixel shader, which is responsible for calculating shadows and effects that determine the final pixel color. This work is situated within the context of the "Ds" class library, a tool developed during a Computer Graphics course that utilizes rasterization via OpenGL, a common graphics API in academia. In this library, the material of the actors currently uses a single fragment shader that applies the Phong lighting model, with its modifiable properties exposed in the graphical interface. Therefore, the objective of this work is to extend this functionality, allowing materials to use different shaders, including user-defined ones. This requires the interface to be constructed dynamically based on the specific properties of the shader selected for a given material. Furthermore, it involves rewriting the rendering loop to ensure each actor is rendered with its respective shader within the same scene.