From 12ba1acbd1f0641a441246aa5a2a49afe72ecfcb Mon Sep 17 00:00:00 2001
From: cinnaboot <cinnaboot@protonmail.com>
Date: Thu, 28 Jun 2018 16:03:37 -0400
Subject: [PATCH] almost working perspective camera

---
 src/renderer.h | 69 +++++++++++++++++---------------------------------
 1 file changed, 23 insertions(+), 46 deletions(-)

diff --git a/src/renderer.h b/src/renderer.h
index eeed4a7..e9d405f 100644
--- a/src/renderer.h
+++ b/src/renderer.h
@@ -18,6 +18,11 @@
 #include "hexlib.h"
 #include "hexgame.h"
 
+#if 0
+	#define PROJ_TYPE ORTHOGRAPHIC
+#else
+	#define PROJ_TYPE PERSPECTIVE
+#endif
 
 const char * VERTEX_SHADER_CODE =
 	"#version 330 core\n"
@@ -82,6 +87,8 @@ enum projection_type
 struct camera
 {
 	glm::vec3 position;
+	float hAngle;
+	float vAngle;
 	glm::vec3 target;
 	glm::vec3 forward;
 	glm::vec3 up;
@@ -275,44 +282,23 @@ initMatrices(projection_type p)
 
 		g_camera.position = glm::vec3(640,0,100); 
 		g_camera.target = glm::vec3(640,500,0);
+		// inital rotation should match target direction
+		glm::vec3 &p = g_camera.position;
+		glm::vec3 &t = g_camera.target;
+		g_camera.hAngle = 0;
+		g_camera.vAngle = glm::atan((p.z - t.z) / (p.y - t.y));
+
 		g_camera.up = glm::vec3(0,1,0);
 		g_camera.forward = glm::normalize(g_camera.position - g_camera.target);
 		g_camera.left = glm::normalize(glm::cross(g_camera.up, g_camera.forward));
 		g_camera.up = glm::cross(g_camera.forward, g_camera.left);
 
-		glm::vec3 P, T, U;
-		P = normalize(g_camera.position);
-		T = normalize(g_camera.target);
-		U = normalize(g_camera.up);
-		//g_camera.forward = glm::cross(T - P, U);
-#if 1
 		glm::mat4 mV = glm::lookAt(
 			g_camera.position, // camera position
 			g_camera.target, // look at position
 			g_camera.up // "up" vector
 		);
 		g_scene_matrices.view = mV;
-#else	
-		// get normalized vector from pos to target
-		glm::vec3 N = g_camera.target;
-		glm::normalize(N);
-		//glm::vec3 U = glm::vec3(0,1,0);
-		U = glm::cross(U, N);
-		glm::vec3 V = glm::cross(N, U);
-		glm::mat4 mR = glm::mat4();
-
-		mR[0][0] = U.x; mR[0][1] = U.y; mR[0][2] = U.z; mR[0][3] = 0.f;
-		mR[1][0] = V.x; mR[1][1] = V.y; mR[1][2] = V.z; mR[1][3] = 0.f;
-		mR[2][0] = N.x; mR[2][1] = N.y; mR[2][2] = N.z; mR[2][3] = 0.f;
-		mR[3][0] = 0.f; mR[3][1] = 0.f; mR[3][2] = 0.f; mR[3][3] = 1.f;
-
-		// get translation xfrom
-		glm::vec3 p = g_camera.position;
-		glm::mat4 mT = glm::translate(glm::mat4(1.0f), glm::vec3(-1 * p.x, -1 * p.y, -1 * p.z));
-
-		glm::mat4 mVtemp = mR * mT;
-		//g_scene_matrices.view = mR * mT;
-#endif
 	}
 	else // ORTHO
 	{
@@ -329,12 +315,6 @@ initMatrices(projection_type p)
 	g_scene_matrices.MVP = g_scene_matrices.projection * g_scene_matrices.view * g_scene_matrices.model; 
 }
 
-#if 0
-#define PROJ_TYPE ORTHOGRAPHIC
-#else
-#define PROJ_TYPE PERSPECTIVE
-#endif
-
 bool
 createScene(std::vector<hex_info>* hexes)
 {
@@ -429,22 +409,19 @@ moveCamera(bool up, bool left, bool down, bool right)
 void
 rotateCamera(int32	xrel, int32 yrel)
 {
-#if 1
-	glm::mat4 &m = g_scene_matrices.view;
-	glm::vec3 &c = g_camera.position;
+	camera &c = g_camera;
+	float &h = c.hAngle;
+	float &v = c.vAngle;
+	h += 0.005f * xrel;
+	c.forward = glm::vec3(
+					glm::cos(v) * glm::sin(h),
+					glm::cos(v) * glm::cos(h),
+					glm::sin(v)
+				);
 
-	m = glm::translate(m, glm::vec3(c.x, c.y, c.z));
-	m = glm::rotate(m, glm::radians(0.5f * xrel), glm::vec3(0.f,0.f,1.f));
-	m = glm::translate(m, glm::vec3(-1.f * c.x, -1.f * c.y, -1.f * c.z));
-	g_scene_matrices.MVP = g_scene_matrices.projection * m * g_scene_matrices.model; 
-#else
 	glm::mat4 &m = g_scene_matrices.view;
-	glm::vec3 &c = g_camera.position;
-
-	m = glm::translate(m, glm::vec3(-1.f * c.x, -1.f * c.y, -1.f * c.z));
-	m = glm::rotate(m, glm::radians(0.5f * xrel), glm::vec3(0.f,0.f,1.f));
+	m = glm::lookAt(c.position, c.position + c.forward, c.up);
 	g_scene_matrices.MVP = g_scene_matrices.projection * m * g_scene_matrices.model; 
-#endif
 }
 
 void