diff options
Diffstat (limited to 'src/model_instance.cpp')
| -rw-r--r-- | src/model_instance.cpp | 161 |
1 files changed, 161 insertions, 0 deletions
diff --git a/src/model_instance.cpp b/src/model_instance.cpp new file mode 100644 index 0000000..48703a5 --- /dev/null +++ b/src/model_instance.cpp @@ -0,0 +1,161 @@ +#include "model_instance.hpp" +#include "scene.hpp" +#include <tuple> + +/** +static inline POINT viewportToScreen (POINT *point) { + // Convert a viewport coordinate to screen x, y + return createPoint(fixed_multiply(point->x, fixed_divide(WINDOW_WIDTH << +FIX_SHIFT, viewport_width << FIX_SHIFT)), fixed_multiply(point->y, +fixed_divide(WINDOW_HEIGHT << FIX_SHIFT, viewport_height << FIX_SHIFT)) + ); +} + +static inline POINT projectVertex(VERTEX *vertex) { + // Project a vertex to a point + POINT temp; + if (vertex->z != 0) { + // Make sure we don't divide by zero + temp = createPoint(fixed_multiply(vertex->x, fixed_divide(ZPlane << +FIX_SHIFT, vertex->z)), fixed_multiply(vertex->y, fixed_divide(ZPlane << +FIX_SHIFT, vertex->z)) + ); + } + else { + temp = createPoint(0, 0); + } + temp = viewportToScreen(&temp); + return temp; +} + +void renderInstance(INSTANCE *instance, SDL_Renderer *renderer) { + // Render an instance + // Array for projected points + POINT projected[instance->model->vertices_length]; + // Pointers for transformed vertices + VERTEX *transformed = malloc(sizeof(VERTEX) * +instance->model->vertices_length); + + for (int i = 0; i < instance->model->vertices_length; i++) { + // Apply translation and rotation + *(transformed + i) = *(instance->model->vertices + i); + applyXRotation((transformed + i), *instance->xRotation); + applyYRotation((transformed + i), *instance->yRotation); + applyZRotation((transformed + i), *instance->zRotation); + *(transformed + i) = addVertices((transformed + i), +instance->position); + // Project vertices + projected[i] = projectVertex(transformed + i); + } + VERTEX n, copyV; + // A directional light source + VERTEX playerLight = createVertex(0, 0, -1 << FIX_SHIFT); + normalizeVertex(&playerLight); + TRIANGLE *addr; + FIXED intensity; + COLOR clr; + for (int i = 0; i < instance->model->triangles_length; i++) { + // Render the triangle + addr = (instance->model->triangles + i); + n = computeNormal(transformed, addr); + normalizeVertex(&n); + // Intensity of light on the triangle + intensity = fixed_multiply(dotProduct(&n, &playerLight) + (1 << +FIX_SHIFT), 127 << FIX_SHIFT); copyV = *(transformed + addr->v2); + normalizeVertex(©V); + + // Grayscale color of the triangle from light intensity + clr = createColor(intensity >> FIX_SHIFT, intensity >> FIX_SHIFT, +intensity >> FIX_SHIFT); + + if (dotProduct(&n, ©V) < 0) { + // The triangle is viewable by the camera + drawFilledTriangle( + &(projected[addr->v0]), + &(projected[addr->v1]), + &(projected[addr->v2]), + &clr, + renderer + ); + + } + } + transformed = NULL; + free(transformed); + + + + + static inline void applyXRotation(VERTEX *vertex, FIXED xRotation) { + // Apply rotation to vertex on x-axis + FIXED sinTheta = float_to_fixed(sin(fixed_to_float(xRotation) * (3.14159 / +180))); FIXED cosTheta = float_to_fixed(cos(fixed_to_float(xRotation) * (3.14159 +/ 180))); FIXED y = vertex->y; FIXED z = vertex->z; vertex->y = +fixed_multiply(y, cosTheta) - fixed_multiply(z, sinTheta); vertex->z = +fixed_multiply(z, cosTheta) + fixed_multiply(y, sinTheta); +} + +static inline void applyYRotation(VERTEX *vertex, FIXED yRotation) { + // Apply rotation to vertex on y-axis + FIXED sinTheta = float_to_fixed(sin(fixed_to_float(yRotation) * (3.14159 / +180))); FIXED cosTheta = float_to_fixed(cos(fixed_to_float(yRotation) * (3.14159 +/ 180))); FIXED x = vertex->x; FIXED z = vertex->z; vertex->x = +fixed_multiply(x, cosTheta) + fixed_multiply(z, sinTheta); vertex->z = +fixed_multiply(z, cosTheta) - fixed_multiply(x, sinTheta); +} + +static inline void applyZRotation(VERTEX *vertex, FIXED zRotation) { + // Apply rotation to vertex on z-axis + FIXED sinTheta = float_to_fixed(sin(fixed_to_float(zRotation) * (3.14159 / +180))); FIXED cosTheta = float_to_fixed(cos(fixed_to_float(zRotation) * (3.14159 +/ 180))); FIXED x = vertex->x; FIXED y = vertex->y; vertex->x = +fixed_multiply(x, cosTheta) - fixed_multiply(y, sinTheta); vertex->y = +fixed_multiply(y, cosTheta) + fixed_multiply(x, sinTheta); +} +} + */ + +VECTOR rotate(VECTOR v, VECTOR rot) { + FIXED sin_theta_x, sin_theta_y, sin_theta_z; + FIXED cos_theta_x, cos_theta_y, cos_theta_z; + VECTOR res = {v.x, v.y, v.z}; + + if (rot.x != 0) { + sin_theta_x = lu_sin(rot.x) >> 4; + cos_theta_x = lu_cos(rot.x) >> 4; + res.y = fxmul(res.y, cos_theta_x) - fxmul(res.z, sin_theta_x); + res.z = fxmul(res.z, cos_theta_x) + fxmul(res.y, sin_theta_x); + } + + if (rot.y != 0) { + sin_theta_y = lu_sin(rot.y) >> 4; + cos_theta_y = lu_cos(rot.y) >> 4; + res.x = fxmul(res.x, cos_theta_y) + fxmul(res.z, sin_theta_y); + res.z = fxmul(res.z, cos_theta_y) - fxmul(res.x, sin_theta_y); + } + + if (rot.z != 0) { + sin_theta_z = lu_sin(rot.z) >> 4; + cos_theta_z = lu_cos(rot.z) >> 4; + res.x = fxmul(res.x, cos_theta_z) - fxmul(res.y, sin_theta_z); + res.y = fxmul(res.z, cos_theta_z) + fxmul(res.x, sin_theta_z); + } + + return res; +}; + +void ModelInstance::render(std::shared_ptr<Scene> scene_context) { + usu::vector<VECTOR> transformed(m_mesh->vertices.size()); + usu::vector<POINT> projected(transformed.size()); + + for (std::uint32_t i = 0; i < transformed.size(); i++) { + transformed[i] = rotate(m_mesh->vertices[i], m_rotation); + projected[i] = scene_context->project_2d(m_mesh->vertices[i]); + } + + for (const TRIANGLE triangle : m_mesh->triangles) { + VECTOR v0 = transformed[std::get<0>(triangle.vertex_indices)]; + VECTOR v1 = transformed[std::get<1>(triangle.vertex_indices)]; + VECTOR v2 = transformed[std::get<2>(triangle.vertex_indices)]; + } +} |