camera init from json data

data/scene_schema.json

@@ -39,9 +39,11 @@
 		"camera": {
 			"type": "object",
 			"properties": {
-				"position" : { "$ref": "#/definitions/vector3" },
-				"rotation" : { "$ref": "#/definitions/vector4" }
-			}
+				"position": { "$ref": "#/definitions/vector3" },
+				"target": { "$ref": "#/definitions/vector3" },
+				"up": { "$ref": "#/definitions/vector3" }
+			},
+			"required": ["position", "target", "up"]
 		},
 
 		"hex_grid" : {

data/test_scene.json

@@ -1,16 +1,19 @@
 {
 	"camera" : {
 		"position" : {
-			"x" : 0,
+			"x" : 640,
 			"y" : 0,
+			"z" : 100
+		},
+		"target" : {
+			"x" : 640,
+			"y" : 500,
 			"z" : 0
 		},
-
-		"rotation" : {
+		"up" : {
 			"x" : 0,
-			"y" : 0,
-			"z" : 0,
-			"w" : 0
+			"y" : 1,
+			"z" : 0
 		}
 	},
 
@@ -25,7 +28,7 @@
 			"name" : "catepillar 1",
 			"model_file" : "catepillar.dae",
 			"position" : {
-				"x" : 640,
+				"x" : 740,
 				"y" : 500,
 				"z" : 0
 			},

src/camera.cpp

@@ -0,0 +1,28 @@
+
+#include "camera.h"
+
+
+void
+cameraInitPerspective(camera& cam, glm::vec3 position, glm::vec3 target, glm::vec3 up)
+{
+	cam.position = position;
+	cam.target = target;
+	cam.up = up;
+	cam.projection = glm::infinitePerspective(glm::radians(FOV), ASPECT_RATIO, NEAR_CLIP_PLANE);
+
+	cam.hAngle = 0;
+	cam.vAngle = glm::atan((cam.target.z - cam.position.z) / (cam.target.y - cam.position.y));
+
+	// FIXME: bug, camera always starts with forward pointing at positive 'z' axis
+	cam.forward = glm::normalize(glm::vec3(
+			glm::cos(cam.vAngle) * glm::sin(cam.hAngle),
+			glm::cos(cam.vAngle) * glm::cos(cam.hAngle),
+			glm::sin(cam.vAngle)
+		));
+	cam.left = glm::normalize(glm::cross(cam.up, cam.forward));
+	cam.up = glm::normalize(glm::cross(cam.forward, cam.left)); // get better "up" vector
+
+	cam.view = glm::lookAt(cam.position, cam.position + cam.forward, cam.up);
+	cam.model = glm::mat4(1.0f);
+	cam.MVP = cam.projection * cam.view * cam.model;
+}

src/camera.h

@@ -0,0 +1,41 @@
+
+#pragma once
+#include <glm/glm.hpp>
+#include <glm/gtc/matrix_transform.hpp>
+#include "util.h"
+
+// TODO: move other camera functions here from renderer.h and pass in camera references
+// TODO: store scene matrices on camera struct instead of global in renderer.h
+
+
+#define FOV 60.f
+#define ASPECT_RATIO 16.f/9.f
+#define NEAR_CLIP_PLANE 0.1f
+
+struct camera
+{
+	glm::vec3 position;
+	float hAngle;
+	float vAngle;
+	glm::vec3 target;
+	glm::vec3 forward;
+	glm::vec3 up;
+	glm::vec3 left;
+
+	glm::mat4 model;
+	glm::mat4 view;
+	glm::mat4 projection;
+	glm::mat4 MVP;
+};
+
+enum projection_type
+{
+	PERSPECTIVE,
+	ORTHOGRAPHIC,
+};
+
+
+void cameraInitPerspective(camera& cam, glm::vec3 position, glm::vec3 target, glm::vec3 up);
+void cameraMove(bool up, bool left, bool down, bool right, bool forward, bool backward);
+void CameraRotate(int32	xrel, int32 yrel);
+void cameraRoll(bool CW, bool CCW);

src/hexgame.cpp

@@ -563,7 +563,7 @@ int main(int argc, char* argv[])
 	// testing scene_loader
 
 	if (slLoadFile(DATA_DIR, DEFAULT_SCENE_FILE, SCENE_SCHEMA_FILE,
-				g_game_state->entities, g_game_state->entity_count, 1000))
+				g_game_state->entities, g_game_state->entity_count, 1000, renGetCamera()))
 	{
 		// ???
 	} else {

src/renderer.cpp

@@ -20,7 +20,6 @@
 #include "aixlog.hpp"
 
 #include "hexlib.h"
-#include "hexgame.h"
 #include "renderer.h"
 #include "render_group.h"
 
@@ -49,23 +48,6 @@ typedef struct gl_matrix_info
 	glm::mat4 MVP;
 } gl_matrix_info;
 
-enum projection_type
-{
-	PERSPECTIVE,
-	ORTHOGRAPHIC,
-};
-
-struct camera
-{
-	glm::vec3 position;
-	float hAngle;
-	float vAngle;
-	glm::vec3 target;
-	glm::vec3 forward;
-	glm::vec3 up;
-	glm::vec3 left;
-};
-
 
 // forward declarations
 void initMatrices(projection_type p);
@@ -192,6 +174,12 @@ addTexture(SDL_Handles &handles, const char * path)
 	return true;
 }
 
+camera&
+renGetCamera()
+{
+	return g_camera;
+}
+
 v2f
 getUnprojectedCoords(int32 x, int32 y, int32 vp_width, int32 vp_height)
 {
@@ -222,6 +210,7 @@ createScene(std::vector<hex_info>* hexes, Entity* entities, uint32 entity_count)
 		entities[i].ren_group->shader = g_default_shader;
 	}
 
+	// TODO: rename/alter this now that we init camera in sceneloader
 	initMatrices(PROJ_TYPE);
 
 	if (!initHexGridBuffers(hexes))
@@ -416,6 +405,12 @@ initMatrices(projection_type p)
 
 	if (p == PERSPECTIVE)
 	{
+		// TODO: replace referernces to g_scene_matrices with camera.matrix_name
+		g_scene_matrices.projection = g_camera.projection;
+		g_scene_matrices.view = g_camera.view;
+		//g_scene_matrices.model = g_camera.model;
+		//g_scene_matrices.MVP = g_camera.MVP;
+#if 0
 		g_scene_matrices.projection = glm::infinitePerspective(
 			glm::radians(60.f), // FoV
 			16.f / 9.f, // ascpect ratio
@@ -454,6 +449,7 @@ initMatrices(projection_type p)
 			g_camera.position + g_camera.forward,
 			g_camera.up // "up" vector
 		);
+#endif
 	}
 	else // ORTHO
 	{

src/renderer.h

@@ -5,8 +5,10 @@
 
 #include <glm/glm.hpp>
 
+#include "camera.h"
+#include "entity.h"
 #include "util.h"
-#include "hexgame.h"
+#include "hexgame.h" // TODO: should move hex_info object out of hexgame.h
 
 struct renPointLight
 {
@@ -20,6 +22,7 @@ struct renPointLight
 
 bool initRenderer(SDL_Handles &handles, v2i vpDims);
 bool addTexture(SDL_Handles &handles, const char * path);
+camera& renGetCamera();
 v2f getUnprojectedCoords(int32 x, int32 y, int32 vp_width, int32 vp_height);
 v3f getCameraPosition();
 bool createScene(std::vector<hex_info>* hexes, Entity* entities, uint32 entity_count);

src/scene_loader.cpp

@@ -15,6 +15,8 @@
 
 // forward declarations
 bool parseFile(rapidjson::Document& doc, const char* data_dir, const char* file_name);
+glm::vec3 parseVec3(const rapidjson::Value& node);
+glm::vec4 parseVec4(const rapidjson::Value& node);
 bool validateScene(rapidjson::Document& schema_doc, rapidjson::Document& scene_doc,
 		const char* scene_file);
 
@@ -28,7 +30,8 @@ slLoadFile(
 		const char* schema_file,
 		Entity* entity_array,
 		uint& entity_count,
-		uint max_entities)
+		uint max_entities,
+		camera& cam)
 {
 	if (entity_array == nullptr) {
 		LOG(ERROR) << "entity array not initialized\n";
@@ -44,31 +47,34 @@ slLoadFile(
 		return false;
 
 	// camera
-	const rapidjson::Value& cam = doc["camera"];
+	const rapidjson::Value& json_cam = doc["camera"];
+	cameraInitPerspective(cam,
+			parseVec3(json_cam["position"]),
+			parseVec3(json_cam["target"]),
+			parseVec3(json_cam["up"])
+		);
 
 
 	// hex grid
 
 	// entities
-	const rapidjson::Value& e = doc["entities"];
-	if (e.Size() > max_entities) {
-		LOG(ERROR) << "entity count: " << e.Size() << ", was more than max_entities: "
+	const rapidjson::Value& entities = doc["entities"];
+	if (entities.Size() > max_entities) {
+		LOG(ERROR) << "entity count: " << entities.Size() << ", was more than max_entities: "
 			<< max_entities << "\n";
 		return false;
 	}
 
-	for (uint i = 0; i < e.Size(); i++) {
+	for (uint i = 0; i < entities.Size(); i++) {
 		meMeshGroup mg;
 		std::string model_path;
-		model_path.append(data_dir).append("/").append(e[i]["model_file"].GetString());
+		model_path.append(data_dir).append("/").append(entities[i]["model_file"].GetString());
 
 		if (meLoadFromFile(model_path.c_str(), mg)) {
-			Entity& e = entity_array[entity_count];
+			Entity& e = entity_array[i];
 			e.mesh_group = mg;
-			//
-			e.scale = glm::vec3(10,10,10);
-			e.translation = glm::vec3(640, 500, 0);
-			//
+			e.scale = parseVec3(entities[i]["scale"]);
+			e.translation = parseVec3(entities[i]["position"]);
 		} else {
 			LOG(ERROR) << "Error loading mesh file\n";
 			return false;
@@ -122,8 +128,31 @@ validateScene(rapidjson::Document& schema_doc, rapidjson::Document& scene_doc, c
 		LOG(ERROR) << "Invalid Document: " << sb.GetString() << "\n";
 		return false;
 	}
-	
+
 	LOG(INFO) << "scene file: " << scene_file << " passed schema validation\n";
 
 	return true;
 }
+
+glm::vec3
+parseVec3(const rapidjson::Value& node)
+{
+	glm::vec3 v3;
+	v3.x = node["x"].GetFloat();
+	v3.y = node["y"].GetFloat();
+	v3.z = node["z"].GetFloat();
+
+	return v3;
+}
+
+glm::vec4
+parseVec4(const rapidjson::Value& node)
+{
+	glm::vec4 v4;
+	v4.x = node["x"].GetFloat();
+	v4.y = node["y"].GetFloat();
+	v4.z = node["z"].GetFloat();
+	v4.w = node["w"].GetFloat();
+
+	return v4;
+}

src/scene_loader.h

@@ -1,4 +1,5 @@
 
+#include "camera.h"
 #include "util.h"
 
 /*
@@ -10,4 +11,5 @@ bool slLoadFile(
 		const char* schema_file,
 		Entity* entity_array,
 		uint& entity_count,
-		uint max_entities);
+		uint max_entities,
+		camera& cam);

src/util.cpp

@@ -10,6 +10,8 @@
 const uint MAX_FILESIZE = 2 * 1024 * 1024; // 2MB
 const uint MAX_STRING_LENGTH = 1024;
 
+// TODO: don't use ftell() to get filesize
+// 	https://wiki.sei.cmu.edu/confluence/display/c/FIO19-C.+Do+not+use+fseek%28%29+and+ftell%28%29+to+compute+the+size+of+a+regular+file
 char *
 utilDumpTextFile(const char* filename)
 {
@@ -28,7 +30,7 @@ utilDumpTextFile(const char* filename)
 
 	std::fread(buf, sizeof(char), length, fp);
 	// TODO: check fp w/ ferror() here
-	
+
 	return buf;
 }