add panini projection (#288)

engine/client/render.h

@@ -236,11 +236,12 @@ typedef enum {
 typedef enum
 {
 	PROJ_STANDARD			= 0,
-	PROJ_STEREOGRAPHIC		= 1,	//aka panini
+	PROJ_STEREOGRAPHIC		= 1,
 	PROJ_FISHEYE			= 2,	//standard fisheye
 	PROJ_PANORAMA			= 3,	//for nice panoramas
 	PROJ_LAEA				= 4,	//lambert azimuthal equal-area 
-	PROJ_EQUIRECTANGULAR	= 5		//projects a sphere into 2d. used by vr screenshots.
+	PROJ_EQUIRECTANGULAR	= 5,	//projects a sphere into 2d. used by vr screenshots.
+	PROJ_PANINI       = 6		//like stereographic, but vertical lines stay straight.
 } qprojection_t;
 
 typedef struct {

engine/client/view.c

@@ -27,7 +27,7 @@ Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
 
 #include <ctype.h> // for isdigit();
 
-cvar_t r_projection = CVARD("r_projection", "0", "0: regular perspective.\n1: stereographic (aka: pannini).\n2: fisheye.\n3: panoramic.\n4: lambert azimuthal equal-area.\n5: Equirectangular");
+cvar_t r_projection = CVARD("r_projection", "0", "0: regular perspective.\n1: stereographic.\n2: fisheye.\n3: panoramic.\n4: lambert azimuthal equal-area.\n5: equirectangular.\n6: panini.");
 cvar_t ffov = CVARFD("ffov", "", 0, "Allows you to set a specific field of view for when a custom projection is specified. If empty, will use regular fov cvar, which might get messy.");
 #if defined(_WIN32) && !defined(MINIMAL)
 //amusing gimmick / easteregg.

engine/gl/gl_rmain.c

@@ -1783,6 +1783,26 @@ qboolean R_RenderScene_Cubemap(void)
 		}
 #endif
 		break;
+	case PROJ_PANINI:
+		shader = R_RegisterShader("postproc_panini", SUF_NONE,
+				"{\n"
+					"program postproc_panini\n"
+					"{\n"
+						"map $sourcecube\n"
+					"}\n"
+				"}\n"
+				);
+
+		facemask |= 1<<4; /*front view*/
+		if (ffov.value > 70)
+		{
+			facemask |= (1<<0) | (1<<1); /*side/top*/
+			if (ffov.value > 85)
+				facemask |= (1<<2) | (1<<3); /*bottom views*/
+			if (ffov.value > 300)
+				facemask |= 1<<5; /*back view*/
+		}
+		break;
 	}
 
 	//FIXME: we should be able to rotate the view

engine/shaders/Makefile

@@ -6,7 +6,7 @@ VKSDKPATH ?= ~/VulkanSDK/1.1.73.0/x86_64/bin/
 
 all:
 
-NAMES=	fixedemu	fixedemu_flat altwater	bloom_blur	bloom_filter	bloom_final	colourtint	crepuscular_opaque	crepuscular_rays	crepuscular_sky	depthonly	default2d	defaultadditivesprite		defaultskin	defaultsky	defaultskybox	defaultfill	defaultsprite	defaultwall	defaultwarp	defaultgammacb	drawflat_wall	lpp_depthnorm	lpp_light	lpp_wall	postproc_fisheye	postproc_panorama	postproc_laea	postproc_stereographic	postproc_equirectangular	fxaa	underwaterwarp	menutint	terrain	rtlight
+NAMES=	fixedemu	fixedemu_flat altwater	bloom_blur	bloom_filter	bloom_final	colourtint	crepuscular_opaque	crepuscular_rays	crepuscular_sky	depthonly	default2d	defaultadditivesprite		defaultskin	defaultsky	defaultskybox	defaultfill	defaultsprite	defaultwall	defaultwarp	defaultgammacb	drawflat_wall	lpp_depthnorm	lpp_light	lpp_wall	postproc_fisheye	postproc_panorama	postproc_laea	postproc_stereographic	postproc_equirectangular   postproc_panini	fxaa	underwaterwarp	menutint	terrain	rtlight
 
 
 ALLNAMES+=$(foreach v,$(NAMES),glsl/$v.glsl)

engine/shaders/generatebuiltinsl.c

@@ -38,6 +38,7 @@ char shaders[][64] =
 	"postproc_laea",
 	"postproc_stereographic",
 	"postproc_equirectangular",
+	"postproc_panini",
 	"postproc_ascii",
 	"fxaa",
 	"underwaterwarp",

engine/shaders/glsl/postproc_panini.glsl

@@ -0,0 +1,37 @@
+!!cvarf ffov
+!!samps screen:samplerCube=0
+
+//panini view rendering, for high fovs that are still playable.
+
+#ifdef VERTEX_SHADER
+attribute vec2 v_texcoord;
+varying vec2 texcoord;
+uniform float cvar_ffov;
+void main()
+{
+	texcoord = v_texcoord.xy;
+
+	//make sure the ffov cvar actually does something meaningful
+	texcoord *= cvar_ffov / 90.0;
+
+	gl_Position = ftetransform();
+}
+#endif
+#ifdef FRAGMENT_SHADER
+varying vec2 texcoord;
+void main()
+{
+	vec3 tc;
+	vec2 d;
+	vec2 ang;
+	d = texcoord;	
+
+	//compute the 2d->3d projection
+	float div = 1.0 + d.x*d.x + d.y*d.y;
+	tc.x = 2.0*d.x/div;
+	tc.y = -d.y;
+	tc.z = -(-1.0 + d.x*d.x + d.y*d.y)/div;
+
+	gl_FragColor = textureCube(s_screen, tc);
+}
+#endif

engine/shaders/glsl/postproc_stereographic.glsl

@@ -21,9 +21,9 @@ void main()
 varying vec2 texcoord;
 void main()
 {
-	vec3 tc;	
-	vec2 d;	
-	vec2 ang;	
+	vec3 tc;
+	vec2 d;
+	vec2 ang;
 	d = texcoord;	
 
 	//compute the 2d->3d projection

engine/vk/vk_init.c

@@ -2687,6 +2687,26 @@ static qboolean VK_R_RenderScene_Cubemap(struct vk_rendertarg *fb)
 		}
 #endif
 		break;
+	case PROJ_PANINI:
+		shader = R_RegisterShader("postproc_panini", SUF_NONE,
+				"{\n"
+					"program postproc_panini\n"
+					"{\n"
+						"map $sourcecube\n"
+					"}\n"
+				"}\n"
+				);
+
+		facemask |= 1<<4; /*front view*/
+		if (ffov.value > 70)
+		{
+			facemask |= (1<<0) | (1<<1); /*side/top*/
+			if (ffov.value > 85)
+				facemask |= (1<<2) | (1<<3); /*bottom views*/
+			if (ffov.value > 300)
+				facemask |= 1<<5; /*back view*/
+		}
+		break;
 	}
 
 	if (!shader || !shader->prog)

quakec/menusys/menu/options_effects.qc

@@ -96,11 +96,12 @@ nonstatic void(mitem_desktop desktop) M_Options_Effects =
 																)),	fl, [0, pos], [0, 8]); pos += 8;
 		fr.add(menuitemcombo_spawn(_("View Projection"),		"r_projection",			'280 8', _(
 																			"0	\"Standard\" "
-																			"1	\"Stereographic / Pannini\" "
+																			"1	\"Stereographic\" "
 																			"2	\"Fish-Eye\" "
 																			"3	\"Panoramic\" "
 																			"4	\"Lambert Azimuthal Equal-Area\" "
 																			"5	\"Equirectangular\" "
+																			"6	\"Panini\" "
 																)),	fl, [0, pos], [0, 8]); pos += 8;
 		fr.add(menuitemcombo_spawn(_("View Projection Fov"),		"ffov",				'280 8', _(
 																			"90	\"Normal\" "