fix: selecting UBO as storage buffer should not remove the SSBO suppo…

…rt flag, this flag is important to decide the shader version directive to use. With UBO set, the version was set as 330 core and some mods (Doom PBR) were complaining about unsupported features.

Also whether to use shadowmap should not be conditioned by the lack of support for the SSBO, shadowmap works just fine with version 330 core

Also add gl_no_ssbo and gl_no_clip_planes to disable support to these features for debugging purpose

src/common/rendering/gl/gl_shader.cpp

@@ -399,18 +399,15 @@ bool FShader::Load(const char * name, const char * vert_prog_lump, const char *
 	assert(screen->mBones != NULL);
 
 
-	if ((gl.flags & RFL_SHADER_STORAGE_BUFFER) && screen->allowSSBO())
 #ifdef __MOBILE__
-		vp_comb << "#version 310 es\n#define SUPPORTS_SHADOWMAPS\n";
+	vp_comb << "#version 310 es\n";
 #else
-		vp_comb << "#version 430 core\n#define SUPPORTS_SHADOWMAPS\n";
-#endif
+	if ((gl.flags & RFL_SHADER_STORAGE_BUFFER) && screen->allowSSBO())
+		vp_comb << "#version 430 core\n";
 	else 
-#ifdef __MOBILE__
-		vp_comb << "#version 310 es\n";
-#else
 		vp_comb << "#version 330 core\n";
 #endif
+	vp_comb << "#define SUPPORTS_SHADOWMAPS\n";
 
 	bool lightbuffertype = screen->mLights->GetBufferType();
 	if (!lightbuffertype)

src/common/rendering/gl_load/gl_interface.cpp

@@ -142,8 +142,7 @@ void gl_LoadExtensions()
 	gl_version = 3.31;
 	gl.flags |= RFL_NO_CLIP_PLANES;
 	gl.flags |= RFL_INVALIDATE_BUFFER;
-	if (gl_storage_buffer_type == 1)
-		gl.flags |= RFL_SHADER_STORAGE_BUFFER;
+	gl.flags |= RFL_SHADER_STORAGE_BUFFER;
 #endif
 	// Don't even start if it's lower than 2.0 or no framebuffers are available (The framebuffer extension is needed for glGenerateMipmapsEXT!)
 	if (gl_version < 3.3f)
@@ -185,12 +184,15 @@ void gl_LoadExtensions()
 	}
 
 
-	if (gl_storage_buffer_type != 1)
+	if (gl_no_ssbo)
 		gl.flags &= ~RFL_SHADER_STORAGE_BUFFER;
 
 	if (gl_no_persistent_buffer)
 		gl.flags &= ~RFL_BUFFER_STORAGE;
 
+	if (gl_no_clip_planes)
+		gl.flags |= RFL_NO_CLIP_PLANES;
+
 	if (gl_version >= 4.3f || CheckExtension("GL_ARB_invalidate_subdata")) gl.flags |= RFL_INVALIDATE_BUFFER;
 	if (gl_version >= 4.3f || CheckExtension("GL_KHR_debug")) gl.flags |= RFL_DEBUG;
 

src/common/rendering/hwrenderer/data/hw_cvars.cpp

@@ -155,4 +155,6 @@ CUSTOM_CVAR (Int, gl_storage_buffer_type, 1, CVAR_ARCHIVE | CVAR_GLOBALCONFIG |
 	Printf("You must restart " GAMENAME " for this change to take effect.\n");
 }
 
-CVARD(Bool, gl_no_persistent_buffer, false, 0, "Only used to test mobile buffer")
+CVARD(Bool, gl_no_persistent_buffer, false, 0, "Disable persistent buffer storage support")
+CVARD(Bool, gl_no_clip_planes, false, 0, "Disable clip planes support")
+CVARD(Bool, gl_no_ssbo, false, 0, "Disable SSBO support")

src/common/rendering/hwrenderer/data/hw_cvars.h

@@ -68,4 +68,6 @@ EXTERN_CVAR(Bool, gl_brightfog)
 EXTERN_CVAR(Bool, gl_lightadditivesurfaces)
 EXTERN_CVAR(Bool, gl_notexturefill)
 
-EXTERN_CVAR(Bool, gl_no_persistent_buffer)
+EXTERN_CVAR(Bool, gl_no_persistent_buffer)
+EXTERN_CVAR(Bool, gl_no_clip_planes)
+EXTERN_CVAR(Bool, gl_no_ssbo)

src/common/rendering/v_video.h

@@ -89,6 +89,7 @@ EXTERN_CVAR(Int, win_y)
 EXTERN_CVAR(Int, win_w)
 EXTERN_CVAR(Int, win_h)
 EXTERN_CVAR(Bool, win_maximized)
+EXTERN_CVAR(Int, gl_storage_buffer_type)
 
 struct FColormap;
 enum FTextureFormat : uint32_t;
@@ -182,7 +183,7 @@ class DFrameBuffer
 	// SSBOs have quite worse performance for read only data, so keep this around only as long as Vulkan has not been adapted yet.
 	bool useSSBO() 
 	{
-		return IsVulkan() || ((hwcaps & RFL_SHADER_STORAGE_BUFFER) && allowSSBO() && !strstr(vendorstring, "Intel"));
+		return IsVulkan() || ((hwcaps & RFL_SHADER_STORAGE_BUFFER) && allowSSBO() && !strstr(vendorstring, "Intel") && gl_storage_buffer_type == 1);
 	}
 
 	virtual DCanvas* GetCanvas() { return nullptr; }

src/rendering/hwrenderer/hw_entrypoint.cpp

@@ -117,7 +117,7 @@ sector_t* RenderViewpoint(FRenderViewpoint& mainvp, AActor* camera, IntRect* bou
 
 	R_SetupFrame(mainvp, r_viewwindow, camera);
 
-	if (mainview && toscreen && !(camera->Level->flags3 & LEVEL3_NOSHADOWMAP) && camera->Level->HasDynamicLights && gl_light_shadowmap && screen->allowSSBO() && (screen->hwcaps & RFL_SHADER_STORAGE_BUFFER))
+	if (mainview && toscreen && !(camera->Level->flags3 & LEVEL3_NOSHADOWMAP) && camera->Level->HasDynamicLights && gl_light_shadowmap)
 	{
 		screen->SetAABBTree(camera->Level->aabbTree);
 		screen->mShadowMap.SetCollectLights([=] {