Files
OpenSpace/modules/globebrowsing/meshes/clipmapgrid.cpp
2016-10-18 15:40:27 +02:00

447 lines
15 KiB
C++

/*****************************************************************************************
* *
* OpenSpace *
* *
* Copyright (c) 2014-2016 *
* *
* Permission is hereby granted, free of charge, to any person obtaining a copy of this *
* software and associated documentation files (the "Software"), to deal in the Software *
* without restriction, including without limitation the rights to use, copy, modify, *
* merge, publish, distribute, sublicense, and/or sell copies of the Software, and to *
* permit persons to whom the Software is furnished to do so, subject to the following *
* conditions: *
* *
* The above copyright notice and this permission notice shall be included in all copies *
* or substantial portions of the Software. *
* *
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, *
* INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A *
* PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT *
* HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF *
* CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE *
* OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. *
****************************************************************************************/
#include <modules/globebrowsing/meshes/clipmapgrid.h>
#include <ghoul/opengl/ghoul_gl.h>
namespace {
const std::string _loggerCat = "ClipMapGrid";
}
namespace openspace {
namespace globebrowsing {
//////////////////////////////////////////////////////////////////////////////////////////
// CLIPMAP GRID (Abstract class) //
//////////////////////////////////////////////////////////////////////////////////////////
ClipMapGrid::ClipMapGrid(unsigned int segments)
: Grid(
segments,
segments,
TriangleSoup::Positions::No,
TriangleSoup::TextureCoordinates::Yes,
TriangleSoup::Normals::No)
{}
ClipMapGrid::~ClipMapGrid()
{}
int ClipMapGrid::xSegments() const {
return segments();
}
int ClipMapGrid::ySegments() const {
return segments();
}
int ClipMapGrid::segments() const {
return _xSegments;
}
//////////////////////////////////////////////////////////////////////////////////////////
// OUTER CLIPMAP GRID //
//////////////////////////////////////////////////////////////////////////////////////////
OuterClipMapGrid::OuterClipMapGrid(unsigned int segments)
: ClipMapGrid(segments)
{
_geometry = std::unique_ptr<TriangleSoup>(new TriangleSoup(
CreateElements(segments, segments),
TriangleSoup::Positions::No,
TriangleSoup::TextureCoordinates::Yes,
TriangleSoup::Normals::No));
_geometry->setVertexTextureCoordinates(CreateTextureCoordinates(segments, segments));
}
OuterClipMapGrid::~OuterClipMapGrid()
{
}
size_t OuterClipMapGrid::numElements(int segments)
{
int numElementsInTotalSquare = 6 * (segments + 1) * (segments + 1);
int numElementsInHole = 6 * (segments / 4 * segments / 4);
return numElementsInTotalSquare - numElementsInHole;
}
size_t OuterClipMapGrid::numVerticesBottom(int segments)
{
return (segments + 1 + 2) * (segments / 4 + 1 + 1);
}
size_t OuterClipMapGrid::numVerticesLeft(int segments)
{
return (segments / 4 + 1 + 1) * (segments / 2 + 1);
}
size_t OuterClipMapGrid::numVerticesRight(int segments)
{
return (segments / 4 + 1 + 1) * (segments / 2 + 1);
}
size_t OuterClipMapGrid::numVerticesTop(int segments)
{
return (segments + 1 + 2) * (segments / 4 + 1 + 1);
}
size_t OuterClipMapGrid::numVertices(int segments)
{
return numVerticesBottom(segments) +
numVerticesLeft(segments) +
numVerticesRight(segments) +
numVerticesTop(segments);
}
void OuterClipMapGrid::validate(int xRes, int yRes) {
ghoul_assert(xRes == yRes,
"segments must be equal in x and in y. ");
int segments = xRes;
ghoul_assert(segments >= 8,
"segments must be at least 8. (" << segments << ")");
ghoul_assert(segments == pow(2, int(log2(segments))),
"segments must be a power of 2. (" << segments << ")");
}
std::vector<GLuint> OuterClipMapGrid::CreateElements(int xRes, int yRes) {
validate(xRes, yRes);
int segments = xRes;
std::vector<GLuint> elements;
elements.reserve(numElements(segments));
// The clipmap geometry is built up by four parts as follows:
// 0 = Bottom part
// 1 = Left part
// 2 = Right part
// 3 = Top part
//
// 33333333
// 33333333
// 11 22
// 11 22
// 00000000
// 00000000
// x v01---v11 x ..
// | / |
// x v00---v10 x ..
//
// x x x x ..
// : : : :
unsigned int previousVerts[4];
previousVerts[0] = 0;
previousVerts[1] = previousVerts[0] + numVerticesBottom(segments);
previousVerts[2] = previousVerts[1] + numVerticesLeft(segments);
previousVerts[3] = previousVerts[2] + numVerticesRight(segments);
// Build the bottom part of the clipmap geometry
for (unsigned int y = 0; y < segments / 4 + 1; y++) {
for (unsigned int x = 0; x < segments + 2; x++) {
GLuint v00 = previousVerts[0] + (y + 0) * (segments + 3) + x + 0;
GLuint v10 = previousVerts[0] + (y + 0) * (segments + 3) + x + 1;
GLuint v01 = previousVerts[0] + (y + 1) * (segments + 3) + x + 0;
GLuint v11 = previousVerts[0] + (y + 1) * (segments + 3) + x + 1;
elements.push_back(v00);
elements.push_back(v10);
elements.push_back(v11);
elements.push_back(v00);
elements.push_back(v11);
elements.push_back(v01);
}
}
// Build the left part of the clipmap geometry
for (unsigned int y = 0; y < segments / 2; y++) {
for (unsigned int x = 0; x < segments / 4 + 1; x++) {
GLuint v00 = previousVerts[1] + (y + 0) * (segments / 4 + 2) + x + 0;
GLuint v10 = previousVerts[1] + (y + 0) * (segments / 4 + 2) + x + 1;
GLuint v01 = previousVerts[1] + (y + 1) * (segments / 4 + 2) + x + 0;
GLuint v11 = previousVerts[1] + (y + 1) * (segments / 4 + 2) + x + 1;
elements.push_back(v00);
elements.push_back(v10);
elements.push_back(v11);
elements.push_back(v00);
elements.push_back(v11);
elements.push_back(v01);
}
}
// Build the left part of the clipmap geometry
for (unsigned int y = 0; y < segments / 2; y++) {
for (unsigned int x = 0; x < segments / 4 + 1; x++) {
GLuint v00 = previousVerts[2] + (y + 0) * (segments / 4 + 2) + x + 0;
GLuint v10 = previousVerts[2] + (y + 0) * (segments / 4 + 2) + x + 1;
GLuint v01 = previousVerts[2] + (y + 1) * (segments / 4 + 2) + x + 0;
GLuint v11 = previousVerts[2] + (y + 1) * (segments / 4 + 2) + x + 1;
elements.push_back(v00);
elements.push_back(v10);
elements.push_back(v11);
elements.push_back(v00);
elements.push_back(v11);
elements.push_back(v01);
}
}
// Build the left part of the clipmap geometry
for (unsigned int y = 0; y < segments / 4 + 1; y++) {
for (unsigned int x = 0; x < segments + 2; x++) {
GLuint v00 = previousVerts[3] + (y + 0) * (segments + 3) + x + 0;
GLuint v10 = previousVerts[3] + (y + 0) * (segments + 3) + x + 1;
GLuint v01 = previousVerts[3] + (y + 1) * (segments + 3) + x + 0;
GLuint v11 = previousVerts[3] + (y + 1) * (segments + 3) + x + 1;
elements.push_back(v00);
elements.push_back(v10);
elements.push_back(v11);
elements.push_back(v00);
elements.push_back(v11);
elements.push_back(v01);
}
}
return elements;
}
std::vector<glm::vec4> OuterClipMapGrid::CreatePositions(int xRes, int yRes)
{
validate(xRes, yRes);
int segments = xRes;
std::vector<glm::vec4> positions;
positions.reserve(numVertices(segments));
std::vector<glm::vec2> templateTextureCoords = CreateTextureCoordinates(xRes, yRes);
// Copy from 2d texture coordinates and use as template to create positions
for (unsigned int i = 0; i < templateTextureCoords.size(); i++) {
positions.push_back(
glm::vec4(
templateTextureCoords[i].x,
templateTextureCoords[i].y,
0,
1));
}
return positions;
}
std::vector<glm::vec2> OuterClipMapGrid::CreateTextureCoordinates(int xRes, int yRes){
validate(xRes, yRes);
int segments = xRes;
std::vector<glm::vec2> textureCoordinates;
textureCoordinates.reserve(numVertices(segments));
// Build the bottom part of the clipmap geometry
for (int y = -1; y < segments / 4 + 1; y++) {
for (int x = -1; x < segments + 2; x++) {
textureCoordinates.push_back(glm::vec2(
static_cast<float>(x) / segments,
static_cast<float>(y) / segments));
}
}
// Build the left part of the clipmap geometry
for (int y = segments / 4; y < 3 * segments / 4 + 1; y++) {
for (int x = -1; x < segments / 4 + 1; x++) {
textureCoordinates.push_back(glm::vec2(
static_cast<float>(x) / segments,
static_cast<float>(y) / segments));
}
}
// Build the right part of the clipmap geometry
for (int y = segments / 4; y < 3 * segments / 4 + 1; y++) {
for (int x = 3 * segments / 4; x < segments + 2; x++) {
float u = static_cast<float>(x) / segments;
float v = static_cast<float>(y) / segments;
textureCoordinates.push_back(glm::vec2(u, v));
}
}
// Build the top part of the clipmap geometry
for (int y = 3 * segments / 4; y < segments + 2; y++) {
for (int x = -1; x < segments + 2; x++) {
textureCoordinates.push_back(glm::vec2(
static_cast<float>(x) / segments,
static_cast<float>(y) / segments));
}
}
return textureCoordinates;
}
std::vector<glm::vec3> OuterClipMapGrid::CreateNormals(int xRes, int yRes) {
validate(xRes, yRes);
int segments = xRes;
std::vector<glm::vec3> normals;
normals.reserve(numVertices(segments));
for (int y = -1; y < segments + 2; y++) {
for (int x = -1; x < segments + 2; x++) {
normals.push_back(glm::vec3(0, 0, 1));
}
}
return normals;
}
//////////////////////////////////////////////////////////////////////////////////////////
// INNER CLIPMAP GRID //
//////////////////////////////////////////////////////////////////////////////////////////
InnerClipMapGrid::InnerClipMapGrid(unsigned int segments)
: ClipMapGrid(segments)
{
_geometry = std::unique_ptr<TriangleSoup>(new TriangleSoup(
CreateElements(segments, segments),
TriangleSoup::Positions::No,
TriangleSoup::TextureCoordinates::Yes,
TriangleSoup::Normals::No));
_geometry->setVertexTextureCoordinates(CreateTextureCoordinates(segments, segments));
}
InnerClipMapGrid::~InnerClipMapGrid()
{
}
size_t InnerClipMapGrid::numElements(int segments)
{
return segments * segments * 6;
}
size_t InnerClipMapGrid::numVertices(int segments)
{
return (segments + 1) * (segments + 1);
}
void InnerClipMapGrid::validate(int xRes, int yRes) {
ghoul_assert(xRes == yRes,
"segments must be equal in x and in y. ");
int segments = xRes;
ghoul_assert(segments >= 1,
"segments must be at least 1. (" << segments << ")");
}
std::vector<GLuint> InnerClipMapGrid::CreateElements(int xRes, int yRes) {
validate(xRes, yRes);
int segments = xRes;
std::vector<GLuint> elements;
elements.reserve(numElements(segments));
// x v01---v11 x ..
// | / |
// x v00---v10 x ..
//
// x x x x ..
// : : : :
for (unsigned int y = 0; y < segments + 2; y++) {
for (unsigned int x = 0; x < segments + 2; x++) {
GLuint v00 = (y + 0) * (segments + 3) + x + 0;
GLuint v10 = (y + 0) * (segments + 3) + x + 1;
GLuint v01 = (y + 1) * (segments + 3) + x + 0;
GLuint v11 = (y + 1) * (segments + 3) + x + 1;
elements.push_back(v00);
elements.push_back(v10);
elements.push_back(v11);
elements.push_back(v00);
elements.push_back(v11);
elements.push_back(v01);
}
}
return elements;
}
std::vector<glm::vec4> InnerClipMapGrid::CreatePositions(int xRes, int yRes)
{
validate(xRes, yRes);
int segments = xRes;
std::vector<glm::vec4> positions;
positions.reserve(numVertices(segments));
std::vector<glm::vec2> templateTextureCoords = CreateTextureCoordinates(xRes, yRes);
// Copy from 2d texture coordinates and use as template to create positions
for (unsigned int i = 0; i < templateTextureCoords.size(); i++) {
positions.push_back(
glm::vec4(
templateTextureCoords[i].x,
templateTextureCoords[i].y,
0,
1));
}
return positions;
}
std::vector<glm::vec2> InnerClipMapGrid::CreateTextureCoordinates(int xRes, int yRes) {
validate(xRes, yRes);
int segments = xRes;
std::vector<glm::vec2> textureCoordinates;
textureCoordinates.reserve(numVertices(segments));
// Build the bottom part of the clipmap geometry
for (int y = -1; y < segments + 2; y++) {
for (int x = -1; x < segments + 2; x++) {
textureCoordinates.push_back(glm::vec2(
static_cast<float>(x) / segments,
static_cast<float>(y) / segments));
}
}
return textureCoordinates;
}
std::vector<glm::vec3> InnerClipMapGrid::CreateNormals(int xRes, int yRes) {
validate(xRes, yRes);
int segments = xRes;
std::vector<glm::vec3> normals;
normals.reserve(numVertices(segments));
for (int y = -1; y < segments + 2; y++) {
for (int x = -1; x < segments + 2; x++) {
normals.push_back(glm::vec3(0, 0, 1));
}
}
return normals;
}
} // namespace globebrowsing
} // namespace openspace