fix bug with starting camera xform

data/scene_schema.json

@@ -41,9 +41,9 @@
 			"properties": {
 				"position": { "$ref": "#/definitions/vector3" },
 				"target": { "$ref": "#/definitions/vector3" },
-				"up": { "$ref": "#/definitions/vector3" }
+				"world_up": { "$ref": "#/definitions/vector3" }
 			},
-			"required": ["position", "target", "up"]
+			"required": ["position", "target", "world_up"]
 		},
 
 		"hex_grid" : {

data/test_scene.json

@@ -6,14 +6,14 @@
 			"z" : 100
 		},
 		"target" : {
-			"x" : 640,
-			"y" : 500,
+			"x" : -140,
+			"y" : 50,
 			"z" : 0
 		},
-		"up" : {
+		"world_up" : {
 			"x" : 0,
-			"y" : 1,
-			"z" : 0
+			"y" : 0,
+			"z" : 1
 		}
 	},
 

src/camera.cpp

@@ -3,30 +3,29 @@
 
 #include "camera.h"
 
+// TODO: add these props to scene json
 #define MOVE_SPEED 5.f
 #define ROTATE_SPEED 0.005f
 #define CAMERA_Z_CLAMP_ANGLE 85.f
+#define FOV 60.f
+#define ASPECT_RATIO 16.f/9.f
+#define NEAR_CLIP_PLANE 0.1f
+
 
 void
-cameraInitPerspective(camera& cam, glm::vec3 position, glm::vec3 target, glm::vec3 up)
+cameraInitPerspective(camera& cam, glm::vec3 position, glm::vec3 target, glm::vec3 world_up)
 {
 	cam.position = position;
 	cam.target = target;
-	cam.up = up;
+	cam.world_up = world_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));
+	cam.forward = glm::normalize(target - position);
+	cam.left = glm::normalize(glm::cross(cam.world_up, cam.forward));
+	cam.up = glm::normalize(glm::cross(cam.forward, cam.left));
 
-	// FIXME: bug, camera always starts with forward pointing at positive 'z' axis
-	// 	camera position also changes with change to window size
-	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.hAngle = glm::atan(cam.forward.x, cam.forward.y);
+	cam.vAngle = glm::atan(cam.forward.z, cam.forward.y);
 
 	cam.view = glm::lookAt(cam.position, cam.position + cam.forward, cam.up);
 	cam.model = glm::mat4(1.0f);
@@ -119,8 +118,7 @@ cameraRotate(camera& cam, int32	xrel, int32 yrel)
 	);
 
 	glm::normalize(cam.forward);
-	cam.up = glm::vec3(0,0,1);
-	cam.left = glm::normalize(glm::cross(cam.forward, cam.up));
+	cam.left = glm::normalize(glm::cross(cam.forward, cam.world_up));
 	cam.up = glm::normalize(glm::cross(cam.left, cam.forward));
 
 	cam.view = glm::lookAt(cam.position, cam.position + cam.forward, cam.up);

src/camera.h

@@ -4,23 +4,18 @@
 #include <glm/gtc/matrix_transform.hpp>
 #include "util.h"
 
-// TODO: move other camera functions here from renderer.h and pass in camera references
-
-
-// TODO: add these props to scene json
-#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 position;
 	glm::vec3 forward;
 	glm::vec3 up;
 	glm::vec3 left;
+	glm::vec3 target;
+	glm::vec3 world_up;
 
 	glm::mat4 model;
 	glm::mat4 view;
@@ -36,7 +31,7 @@ enum projection_type
 
 
 v2f cameraUnproject(camera& cam, int x, int y, int vp_width, int vp_height);
-void cameraInitPerspective(camera& cam, glm::vec3 position, glm::vec3 target, glm::vec3 up);
+void cameraInitPerspective(camera& cam, glm::vec3 position, glm::vec3 target, glm::vec3 world_up);
 void cameraMove(camera& cam, bool up, bool left, bool down, bool right, bool forward, bool backward);
 void cameraRotate(camera& cam, int32	xrel, int32 yrel);
 void cameraRoll(camera& cam, bool CW, bool CCW);

src/gooey.cpp

@@ -86,18 +86,25 @@ gooRender(SDL_Handles &handles, hexgrid* grid, bool &is_debug, camera* cam)
 	ImGui::Text("is_selecting");
 	ImGui::SameLine(); ImGui::TextUnformatted(grid->is_selecting ? "true" : "false");
 
+	if (ImGui::CollapsingHeader("Camera", ImGuiTreeNodeFlags_DefaultOpen)) {
+		ImGui::Indent();
 		if (ImGui::CollapsingHeader("Camera Position", ImGuiTreeNodeFlags_DefaultOpen)) {
 			ImGui::Text("x: %f", cam->position.x);
 			ImGui::Text("y: %f", cam->position.y);
 			ImGui::Text("z: %f", cam->position.z);
 		}
 
-#if 0
-	// testing SDL_image
-	SDL_Surface* image = handles.texSurfaces[0];
-	ImGui::Image((void*)(intptr_t) image->userdata, ImVec2(image->w, image->h));
-#endif
-	//ImGui::ShowMetricsWindow();
+		if (ImGui::CollapsingHeader("Camera Forward", ImGuiTreeNodeFlags_DefaultOpen)) {
+			ImGui::Text("x: %f", cam->forward.x);
+			ImGui::Text("y: %f", cam->forward.y);
+			ImGui::Text("z: %f", cam->forward.z);
+		}
+
+		ImGui::Spacing();
+		ImGui::Text("hAngle: %f", cam->hAngle);
+		ImGui::Text("vAngle: %f", cam->vAngle);
+		ImGui::Unindent();
+	}
 
 	if (grid->current_hex) {
 		Hex ch = grid->current_hex->hex;

src/hexgame.cpp

@@ -2,9 +2,9 @@
  * TODO:
  * - renderer
  *	- clean up main(), split out initialization and scene loading to new functions
+ *	- move input handling out to new file, controller?
  *	- check over renderer, camera, gooey init after changes
  *	- pass in frame time to camera movement functions to decouple speed from framerate
- *	- attempt to fix bug with starting camera xform
  *	- test camera speed when moving with composite vector
  *		- may be fixed?? need to test by examining camera position between frames
  *			and compare the distance
@@ -23,6 +23,7 @@
  * - use a storage pool for assimp meshes allowing reuse across entities
  * - replace remaining calls to malloc/free with safe(r) function in util.h
  * - add cpu perforcmace counters in render loop
+ * - test YAML for scene loading https://yaml.org/
  * - maybe try deferred rendering at some point to use a ton of lights
  * - check for memory leaks w/ valgrind
  ******************************************************************************/

src/scene_loader.cpp

@@ -105,7 +105,7 @@ slParseCamera(slSceneDoc* sd, camera& cam)
 	cameraInitPerspective(cam,
 		parseVec3(json_cam["position"]),
 		parseVec3(json_cam["target"]),
-		parseVec3(json_cam["up"])
+		parseVec3(json_cam["world_up"])
 	);
 }