fix 3d picking

src/hexgame.cpp

@@ -85,7 +85,9 @@ resetHexes()
 hex_info *
 getSingleHex(int32 x, int32 y)
 {
-	Point p(x, y);
+	v2i dims = g_render_state->viewport_dims;
+	v2f v = getUnprojectedCoords(x, y, dims.x, dims.y);
+	Point p(v.x, v.y);
 	Hex h = hex_round(pixel_to_hex(g_game_state->hex_layout, p));
 	
 	for (hex_info &hxi : *g_game_state->hex_array)

src/renderer.h

@@ -155,6 +155,8 @@ initRenderer(SDL_Handles &handles, v2i vpDims)
 	SDL_GL_SetAttribute(SDL_GL_STENCIL_SIZE, 8);
 	SDL_GL_SetAttribute(SDL_GL_CONTEXT_MAJOR_VERSION, 3);
 	SDL_GL_SetAttribute(SDL_GL_CONTEXT_MINOR_VERSION, 3);
+	SDL_GL_SetAttribute(SDL_GL_MULTISAMPLEBUFFERS, 1);
+	SDL_GL_SetAttribute(SDL_GL_MULTISAMPLESAMPLES, 4);
 	SDL_GL_SetSwapInterval(1);	// vsync
 	SDL_GetCurrentDisplayMode(0, &handles.currentDisplayMode);
 	handles.window = 
@@ -187,6 +189,9 @@ initRenderer(SDL_Handles &handles, v2i vpDims)
 	LOG(INFO)<< "opengl renderer: " << glGetString(GL_RENDERER) << "\n";
 	LOG(INFO) << "opengl version: " << glGetString(GL_VERSION) << "\n";
 	
+	glEnable(GL_DEPTH_TEST);
+	glEnable(GL_LINE_SMOOTH);
+
 	// TODO: blending, these options break the http://www.opengl-tutorial.org tutorials atm
 	// Setup render state: alpha-blending enabled, polygon fill
 #if 1
@@ -239,6 +244,20 @@ addTexture(SDL_Handles &handles, std::string path)
 	return true;
 }
 
+v2f
+getUnprojectedCoords(int32 x, int32 y, int32 vp_width, int32 vp_height)
+{
+	// NOTE: using depth buffer may not be as accurate as doing ray-cast
+	GLfloat depth;
+	glReadPixels(x, y, 1, 1, GL_DEPTH_COMPONENT, GL_FLOAT, &depth);
+	glm::vec4 viewport = glm::vec4(0, 0, vp_width, vp_height);
+	glm::vec3 wincoord = glm::vec3(x, y, depth);
+	glm::vec3 vU = glm::unProject(wincoord, g_scene_matrices.view, g_scene_matrices.projection, viewport);
+	v2f v(vU.x, vU.y);
+
+	return v;
+}
+
 // NOTE: mat_id should match the matrix variable name in the shader source
 bool
 initShaderProgram(gl_render_group &rg, const char * vertex_code, const char * frag_code, const char * mat_id)
@@ -414,6 +433,8 @@ moveCamera(bool up, bool left, bool down, bool right, bool forward, bool backwar
 		v -= r;
 	}
 
+	// TODO: this still doesn't fix side to side movement magnitude when vAngle is
+	// 	close to +- 90 degrees
 	glm::normalize(v);
 	p += (v * MOVE_SPEED);
 	glm::vec3 diff = old - p;