4jcraft/Minecraft.Client/Rendering/Polygon.cpp
2026-03-26 01:10:27 -05:00

71 lines
2.2 KiB
C++

#include "../Platform/stdafx.h"
#include "Polygon.h"
// 4J added for common init code
void _Polygon::_init(VertexArray vertices) {
vertexCount = 0;
_flipNormal = false;
this->vertices = vertices;
vertexCount = vertices.length;
}
_Polygon::_Polygon(VertexArray vertices) { _init(vertices); }
_Polygon::_Polygon(VertexArray vertices, int u0, int v0, int u1, int v1,
float xTexSize, float yTexSize) {
_init(vertices);
// 4J - added - don't assume that u1 > u0, v1 > v0
float us = (u1 > u0) ? (0.1f / xTexSize) : (-0.1f / xTexSize);
float vs = (v1 > v0) ? (0.1f / yTexSize) : (-0.1f / yTexSize);
vertices[0] = vertices[0]->remap(u1 / xTexSize - us, v0 / yTexSize + vs);
vertices[1] = vertices[1]->remap(u0 / xTexSize + us, v0 / yTexSize + vs);
vertices[2] = vertices[2]->remap(u0 / xTexSize + us, v1 / yTexSize - vs);
vertices[3] = vertices[3]->remap(u1 / xTexSize - us, v1 / yTexSize - vs);
}
_Polygon::_Polygon(VertexArray vertices, float u0, float v0, float u1,
float v1) {
_init(vertices);
vertices[0] = vertices[0]->remap(u1, v0);
vertices[1] = vertices[1]->remap(u0, v0);
vertices[2] = vertices[2]->remap(u0, v1);
vertices[3] = vertices[3]->remap(u1, v1);
}
void _Polygon::mirror() {
VertexArray newVertices = VertexArray(vertices.length);
for (unsigned int i = 0; i < vertices.length; i++)
newVertices[i] = vertices[vertices.length - i - 1];
delete[] vertices.data;
vertices = newVertices;
}
void _Polygon::render(Tesselator* t, float scale) {
Vec3 v0 = vertices[1]->pos->vectorTo(*vertices[0]->pos);
Vec3 v1 = vertices[1]->pos->vectorTo(*vertices[2]->pos);
Vec3 n = v1.cross(v0).normalize();
t->begin();
if (_flipNormal) {
t->normal(-(float)n.x, -(float)n.y, -(float)n.z);
} else {
t->normal((float)n.x, (float)n.y, (float)n.z);
}
for (int i = 0; i < 4; i++) {
Vertex* v = vertices[i];
t->vertexUV((float)(v->pos->x * scale), (float)(v->pos->y * scale),
(float)(v->pos->z * scale), (float)(v->u), (float)(v->v));
}
t->end();
}
_Polygon* _Polygon::flipNormal() {
_flipNormal = true;
return this;
}