From 7fa0d777af0285886571b35ac0e632be450fe49e Mon Sep 17 00:00:00 2001
From: Joseph Walton-Rivers <joseph@walton-rivers.uk>
Date: Sat, 20 Nov 2021 19:10:42 +0000
Subject: [PATCH] add heightmap code
---
demo/main.cpp | 18 ++++++-
fggl/CMakeLists.txt | 5 +-
fggl/data/heightmap.cpp | 107 ++++++++++++++++++++++++++++++++++++++
fggl/data/heightmap.h | 44 ++++++++++++++++
fggl/data/model.cpp | 2 +-
fggl/data/model.hpp | 11 ++--
fggl/gfx/ogl/compat.hpp | 24 +++++++--
fggl/gfx/ogl/renderer.cpp | 14 ++++-
fggl/gfx/ogl/renderer.hpp | 6 +++
9 files changed, 215 insertions(+), 16 deletions(-)
create mode 100644 fggl/data/heightmap.cpp
create mode 100644 fggl/data/heightmap.h
diff --git a/demo/main.cpp b/demo/main.cpp
index db2e3c7..e14e2d5 100644
--- a/demo/main.cpp
+++ b/demo/main.cpp
@@ -133,6 +133,20 @@ public:
cameraKeys->rotate_ccw = glfwGetKeyScancode(GLFW_KEY_E);
}
+ {
+ fggl::ecs3::entity_t terrain = m_world.create(false);
+ m_world.add(terrain, types.find(fggl::math::Transform::name));
+
+ auto camTf = m_world.get<fggl::math::Transform>(terrain);
+ camTf->origin( glm::vec3(0.0f, 0.0f, 3.0f) );
+
+ //auto terrainData = m_world.get<fggl::data::HeightMap>(terrain);
+ fggl::data::HeightMap terrainData{};
+ terrainData.clear();
+ terrainData.heightValues[50 * 255 + 50] = 50.0f;
+ m_world.set<fggl::data::HeightMap>(terrain, &terrainData);
+ }
+
// create building prototype
fggl::ecs3::entity_t bunker;
{
@@ -146,7 +160,7 @@ public:
fggl::data::Mesh mesh;
for (int j=-(nSections/2); j<=nSections/2; j++) {
- const auto shapeOffset = glm::vec3( 0.0f, 0.0f, (float)j * 1.0f );
+ const auto shapeOffset = glm::vec3( 0.0f, 0.5f, (float)j * 1.0f );
const auto cubeMat = glm::translate( fggl::math::mat4( 1.0f ) , shapeOffset );
const auto leftSlope = fggl::math::modelMatrix(
@@ -170,7 +184,7 @@ public:
for ( int i=0; i<nCubes; i++ ) {
auto bunkerClone = m_world.copy(bunker);
auto result = m_world.get<fggl::math::Transform>(bunkerClone);
- result->origin( glm::vec3( (float)i * 5.0f, 0.0f, 0.0f) );
+ result->origin( glm::vec3( (float)i * 5.0f + 1.0f, 0.0f, 0.0f) );
}
}
diff --git a/fggl/CMakeLists.txt b/fggl/CMakeLists.txt
index 19de7ba..00b4c99 100644
--- a/fggl/CMakeLists.txt
+++ b/fggl/CMakeLists.txt
@@ -4,12 +4,13 @@ add_library(fggl fggl.cpp
ecs/ecs.cpp
data/model.cpp
data/procedural.cpp
+ data/heightmap.cpp
ecs3/fast/Container.cpp
ecs3/prototype/world.cpp
scenes/Scene.cpp
ecs3/module/module.cpp
- input/camera_input.cpp
-)
+ input/camera_input.cpp data/heightmap.cpp)
+
target_include_directories(fggl PUBLIC ${CMAKE_CURRENT_SOURCE_DIR}/../)
# Graphics backend
diff --git a/fggl/data/heightmap.cpp b/fggl/data/heightmap.cpp
new file mode 100644
index 0000000..1009cb6
--- /dev/null
+++ b/fggl/data/heightmap.cpp
@@ -0,0 +1,107 @@
+//
+// Created by webpigeon on 20/11/2021.
+//
+
+#include <fggl/data/model.hpp>
+#include <fggl/data/heightmap.h>
+
+// adapted from https://www.mbsoftworks.sk/tutorials/opengl4/016-heightmap-pt1-random-terrain/
+
+namespace fggl::data {
+
+ void gridVertexNormals(data::Vertex *locations) {
+ int sizeX = data::heightMaxX;
+ int sizeY = data::heightMaxZ;
+ const int gridOffset = sizeX * sizeY;
+
+ // calculate normals for each triangle
+ math::vec3 triNormals[sizeX * sizeY * 2];
+ for (int i = 0; i < sizeX - 1; i++) {
+ for (int j = 0; j < sizeY - 1; j++) {
+ // calculate vertex
+ const auto &a = locations[i * sizeY + j].posititon;
+ const auto &b = locations[(i + 1) * sizeY + j].posititon;
+ const auto &c = locations[i * sizeY + (j + 1)].posititon;
+ const auto &d = locations[(i + 1) * sizeY + (j + 1)].posititon;
+
+ const auto normalA = glm::cross(b - a, a - d);
+ const auto normalB = glm::cross(d - c, c - b);
+
+ // store the normals
+ int idx1 = idx(i, j, sizeY);
+ int idx2 = idx1 + gridOffset;
+ triNormals[idx1] = glm::normalize(normalA);
+ triNormals[idx2] = glm::normalize(normalB);
+ }
+ }
+
+ // calculate normals for each vertex
+ for (int i = 0; i < sizeX; i++) {
+ for (int j = 0; j < sizeY; j++) {
+ const auto firstRow = (i == 0);
+ const auto firstCol = (j == 0);
+ const auto lastRow = (i == sizeX - 1);
+ const auto lastCol = (i == sizeY - 1);
+
+ auto finalNormal = glm::vec3(0.0f, 0.0f, 0.0f);
+
+ if (!firstRow && !firstCol) {
+ finalNormal += triNormals[idx(i - 1, j - 1, sizeY)];
+ }
+
+ if (!lastRow && !lastCol) {
+ finalNormal += triNormals[idx(i, j, sizeY)];
+ }
+
+ if (!firstRow && lastCol) {
+ finalNormal += triNormals[idx(i - 1, j, sizeY)];
+ finalNormal += triNormals[idx(i - 1, j, sizeY) + gridOffset];
+ }
+
+ if (!lastRow && !firstCol) {
+ finalNormal += triNormals[idx(i, j - 1, sizeY)];
+ finalNormal += triNormals[idx(i, j - 1, sizeY) + gridOffset];
+ }
+
+ locations[idx(i, j, sizeY)].normal = glm::normalize(finalNormal) * -1.0f; //FIXME the normals seem wrong.
+ }
+ }
+ }
+
+ void generateHeightMesh(const data::HeightMap *heights, data::Mesh &mesh) {
+
+ // step 1: convert height data into vertex locations
+ data::Vertex locations[data::heightMaxZ * data::heightMaxZ];
+ for (std::size_t x = 0; x < data::heightMaxX; x++) {
+ for (std::size_t z = 0; z < data::heightMaxZ; z++) {
+ float level = heights->getValue(x, z);
+ auto xPos = float(x);
+ auto zPos = float(z);
+
+ std::size_t idx1 = idx(x, z, data::heightMaxZ);
+ locations[idx1].colour = fggl::math::vec3(1.0f, 1.0f, 1.0f);
+ locations[idx1].posititon = math::vec3(-0.5f + xPos, level, -0.5f - zPos);
+ }
+ }
+ gridVertexNormals(locations);
+
+ mesh.restartVertex = data::heightMaxZ * data::heightMaxX;
+
+ // populate mesh
+ for (auto & location : locations) {
+ mesh.pushVertex(location);
+ }
+
+ for (std::size_t x = 0; x < data::heightMaxX - 1; x++) {
+ for (std::size_t z = 0; z < data::heightMaxZ; z++) {
+ for (int k=0; k < 2; k++) {
+ int idx = (x+k) * data::heightMaxZ + z;
+ mesh.pushIndex(idx);
+ }
+ }
+ mesh.pushIndex(mesh.restartVertex);
+ }
+
+ }
+
+}
diff --git a/fggl/data/heightmap.h b/fggl/data/heightmap.h
new file mode 100644
index 0000000..48908bd
--- /dev/null
+++ b/fggl/data/heightmap.h
@@ -0,0 +1,44 @@
+//
+// Created by webpigeon on 20/11/2021.
+//
+
+#ifndef FGGL_HEIGHTMAP_H
+#define FGGL_HEIGHTMAP_H
+
+#include <cstdint>
+
+namespace fggl::data {
+
+ constexpr std::size_t heightMaxX = 255;
+ constexpr std::size_t heightMaxZ = 255;
+ constexpr float heightSeaLevel = 0.0f;
+
+ struct HeightMap {
+ constexpr static const char name[] = "Heightmap";
+ float heightValues[heightMaxX * heightMaxZ];
+
+ void clear() {
+ for (float & heightValue : heightValues){
+ heightValue = heightSeaLevel;
+ }
+ }
+
+ [[nodiscard]]
+ inline float getValue(std::size_t x, std::size_t z) const {
+ return heightValues[x * heightMaxZ + z];
+ }
+
+ inline void setValue(std::size_t x, std::size_t z, float value) {
+ heightValues[x * heightMaxZ + z] = value;
+ }
+ };
+
+
+ inline int idx(int x, int z, int zMax) {
+ return x * zMax + z;
+ }
+
+ void generateHeightMesh(const data::HeightMap* heights, data::Mesh &mesh);
+}
+
+#endif //FGGL_HEIGHTMAP_H
diff --git a/fggl/data/model.cpp b/fggl/data/model.cpp
index 0cded14..6c0a08a 100644
--- a/fggl/data/model.cpp
+++ b/fggl/data/model.cpp
@@ -9,7 +9,7 @@ Mesh::Mesh() : m_verts(0), m_index(0) {
}
void Mesh::pushIndex(unsigned int idx) {
- assert( idx < m_verts.size() );
+ assert( idx < m_verts.size() || idx == this->restartVertex );
m_index.push_back(idx);
}
diff --git a/fggl/data/model.hpp b/fggl/data/model.hpp
index 2f57d00..bc90ed1 100644
--- a/fggl/data/model.hpp
+++ b/fggl/data/model.hpp
@@ -43,10 +43,12 @@ namespace fggl::data {
*/
inline void push(Vertex vert) {
auto idx = indexOf(vert);
- if ( idx == -1 )
- pushVertex(vert);
- else
- pushIndex(idx);
+ if ( idx == -1 ) {
+ idx = pushVertex(vert);
+ pushIndex(idx);
+ } else {
+ pushIndex(idx);
+ }
}
/**
@@ -97,6 +99,7 @@ namespace fggl::data {
inline Vertex& vertex(int idx) {
return m_verts[idx];
}
+ unsigned int restartVertex;
private:
std::vector<Vertex> m_verts;
diff --git a/fggl/gfx/ogl/compat.hpp b/fggl/gfx/ogl/compat.hpp
index 9c792eb..6108dad 100644
--- a/fggl/gfx/ogl/compat.hpp
+++ b/fggl/gfx/ogl/compat.hpp
@@ -20,9 +20,12 @@
#include <fggl/ecs/ecs.hpp>
#include <utility>
#include <fggl/input/camera_input.h>
+#include <fggl/data/heightmap.h>
namespace fggl::gfx {
+ void generateHeightMesh(data::HeightMap* heightMap, data::Mesh);
+
//
// fake module support - allows us to still RAII
//
@@ -48,9 +51,23 @@ namespace fggl::gfx {
world->set<fggl::gfx::GlRenderToken>(entity, &glMesh);
}
+ void uploadHeightmap(ecs3::World *world, ecs::entity_t entity) {
+ const auto heightmap = world->get<data::HeightMap>(entity);
+
+ data::Mesh tmpMesh{};
+ data::generateHeightMesh(heightmap, tmpMesh);
+ auto glMesh = renderer.upload( tmpMesh );
+
+ auto pipeline = cache.get("phong");
+ glMesh.pipeline = pipeline;
+ glMesh.renderType = GlRenderType::trinagle_strip;
+ world->set<fggl::gfx::GlRenderToken>(entity, &glMesh);
+ }
+
void onLoad(ecs3::ModuleManager& manager, ecs3::TypeRegistry& types) override {
// TODO implement dependencies
types.make<fggl::gfx::StaticMesh>();
+ types.make<fggl::data::HeightMap>();
types.make<fggl::gfx::Camera>();
// FIXME probably shouldn't be doing this...
@@ -62,6 +79,7 @@ namespace fggl::gfx {
// callbacks
auto upload_cb = [this](auto a, auto b) { this->uploadMesh(a, b); };
manager.onAdd<fggl::gfx::StaticMesh>( upload_cb );
+ manager.onAdd<fggl::data::HeightMap>( [this](auto a, auto b) { this->uploadHeightmap(a, b); });
}
};
@@ -110,11 +128,7 @@ namespace fggl::gfx {
auto camera = cameras[0];
// get the models
- auto renderables = ecs.findMatching<fggl::gfx::GlRenderToken>();
-
- for ( auto renderable : renderables ) {
- mod->renderer.render(ecs, camera, dt);
- }
+ mod->renderer.render(ecs, camera, dt);
}
}
diff --git a/fggl/gfx/ogl/renderer.cpp b/fggl/gfx/ogl/renderer.cpp
index eff7e8e..1132df9 100644
--- a/fggl/gfx/ogl/renderer.cpp
+++ b/fggl/gfx/ogl/renderer.cpp
@@ -47,6 +47,7 @@ static GLuint createIndexBuffer(std::vector<uint32_t>& indexData) {
return buffId;
}
+
GlRenderToken MeshRenderer::upload(fggl::data::Mesh& mesh) {
GlRenderToken token{};
glGenVertexArrays(1, &token.vao);
@@ -61,6 +62,7 @@ GlRenderToken MeshRenderer::upload(fggl::data::Mesh& mesh) {
token.buffs[1] = createIndexBuffer( mesh.indexList() );
token.idxOffset = 0;
token.idxSize = mesh.indexCount();
+ token.restartVertex = mesh.restartVertex;
glBindVertexArray(0);
return token;
@@ -116,10 +118,18 @@ void MeshRenderer::render(fggl::ecs3::World& ecs, ecs3::entity_t camera, float d
glUniform3fv( lightID, 1, glm::value_ptr( lightPos ) );
glBindVertexArray( mesh->vao );
- glDrawElements( GL_TRIANGLES, mesh->idxSize, GL_UNSIGNED_INT, reinterpret_cast<void*>(mesh->idxOffset) );
+
+ if ( mesh->renderType == GlRenderType::trinagle_strip) {
+ glEnable(GL_PRIMITIVE_RESTART);
+ glPrimitiveRestartIndex(mesh->restartVertex);
+ }
+
+ glDrawElements( mesh->renderType, mesh->idxSize, GL_UNSIGNED_INT, reinterpret_cast<void*>(mesh->idxOffset) );
+ if ( mesh->renderType == GlRenderType::trinagle_strip) {
+ glDisable(GL_PRIMITIVE_RESTART);
+ }
}
glBindVertexArray(0);
-
}
diff --git a/fggl/gfx/ogl/renderer.hpp b/fggl/gfx/ogl/renderer.hpp
index b13647f..2e900cb 100644
--- a/fggl/gfx/ogl/renderer.hpp
+++ b/fggl/gfx/ogl/renderer.hpp
@@ -9,6 +9,10 @@
namespace fggl::gfx {
+ enum GlRenderType {
+ triangles = GL_TRIANGLES, trinagle_strip = GL_TRIANGLE_STRIP
+ };
+
struct GlRenderToken {
constexpr static const char name[] = "RenderToken";
GLuint vao;
@@ -16,6 +20,8 @@ namespace fggl::gfx {
GLuint idxOffset;
GLuint idxSize;
GLuint pipeline;
+ GLuint restartVertex;
+ GlRenderType renderType = triangles;
};
class GlMeshRenderer {
--
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