Add a geometry flag to ProgramBuilder

It does not generate a geometry shader yet but allows one to be manually
inserted into the program.

diff --git a/source/programbuilder.cpp b/source/programbuilder.cpp
index 829691b61c8fbd8929262fe8a5da6e6404e167ef..affc4cc30e2b26ca109e0c9d4eeebe72c430c407 100644 (file)
--- a/source/programbuilder.cpp
+++ b/source/programbuilder.cpp
@@ -162,11 +162,12 @@ const ProgramBuilder::VariableDefinition ProgramBuilder::standard_variables[] =
        { NO_SCOPE, 0, 0, 0, 0 }
 };
 
-const char ProgramBuilder::interfaces[] = { 0, 0, 0, 0, 0, 'v', 0 };
+const char ProgramBuilder::interfaces[] = { 0, 0, 0, 0, 0, 'v', 'g', 0 };
 
 ProgramBuilder::ProgramBuilder(const StandardFeatures &f):
        features(f),
        feature_flags(features.create_flags()),
+       enabled_scopes((1<<N_SCOPES)-1),
        optimize(true)
 {
        if(!features.custom.empty())
@@ -259,6 +260,9 @@ ProgramBuilder::ProgramBuilder(const StandardFeatures &f):
                }
        }
 
+       if(!features.geometry)
+               enabled_scopes &= ~(1<<GEOMETRY);
+
        if(!features.legacy)
        {
                aliases["texture1D"] = "texture";
@@ -469,7 +473,7 @@ string ProgramBuilder::create_source(const list<ShaderVariable *> &variables, Va
                if(iface&INPUT)
                {
                        const char *qualifier = (features.legacy ? scope==VERTEX ? "attribute" : "varying" : "in");
-                       source += format("%s %s;\n", qualifier, (*i)->create_declaration(interfaces[scope-1]));
+                       source += format("%s %s;\n", qualifier, (*i)->create_declaration(interfaces[previous_scope(scope, enabled_scopes)]));
                }
 
                if(iface&OUTPUT)
@@ -743,9 +747,21 @@ string ProgramBuilder::replace_identifiers(const char *expression, const map<str
        return result;
 }
 
+ProgramBuilder::VariableScope ProgramBuilder::previous_scope(VariableScope scope, unsigned enabled_scopes)
+{
+       while(scope!=NO_SCOPE)
+       {
+               scope = static_cast<VariableScope>(scope-1);
+               if(enabled_scopes&(1<<scope))
+                       break;
+       }
+
+       return scope;
+}
+
 string ProgramBuilder::create_expression(const ShaderVariable &var, const char *loop) const
 {
-       string expr = var.create_expression(loop);
+       string expr = var.create_expression(enabled_scopes, loop);
        return replace_identifiers(expr.c_str(), aliases, true);
 }
 
@@ -762,7 +778,8 @@ ProgramBuilder::StandardFeatures::StandardFeatures():
        shadow(false),
        reflection(false),
        clipping(false),
-       max_clip_planes(1)
+       max_clip_planes(1),
+       geometry(false)
 {
        if(get_gl_api()==OPENGL_ES2)
                legacy = !(get_glsl_version()>=Version(3, 0));
@@ -1075,18 +1092,19 @@ string ProgramBuilder::ShaderVariable::create_declaration(char iface, bool loop)
                return format("%s %s%s", variable->type, resolved_name, array);
 }
 
-string ProgramBuilder::ShaderVariable::create_replacement(VariableScope from_scope, const char *loop) const
+string ProgramBuilder::ShaderVariable::create_replacement(VariableScope from_scope, unsigned enabled_scopes, const char *loop) const
 {
        string replacement = resolved_name;
        InterfaceFlags iface = NO_INTERFACE;
        if(variable)
        {
                iface = get_interface_flags(from_scope);
-               if((iface&INPUT) && interfaces[from_scope-1])
-                       replacement = format("%c_%s", interfaces[from_scope-1], replacement);
+               VariableScope prev_scope = previous_scope(from_scope, enabled_scopes);
+               if((iface&INPUT) && interfaces[prev_scope])
+                       replacement = format("%c_%s", interfaces[prev_scope], replacement);
                else if(inlined)
                {
-                       replacement = create_expression(loop);
+                       replacement = create_expression(enabled_scopes, loop);
                        if(inline_parens)
                                replacement = "("+replacement+")";
                        return replacement;
@@ -1105,12 +1123,12 @@ string ProgramBuilder::ShaderVariable::create_replacement(VariableScope from_sco
        return replacement;
 }
 
-string ProgramBuilder::ShaderVariable::create_expression(const char *loop) const
+string ProgramBuilder::ShaderVariable::create_expression(unsigned enabled_scopes, const char *loop) const
 {
        map<string, string> replace_map;
        for(list<ShaderVariable *>::const_iterator i=referenced_vars.begin(); i!=referenced_vars.end(); ++i)
        {
-               string replacement = (*i)->create_replacement(variable->scope, loop);
+               string replacement = (*i)->create_replacement(variable->scope, enabled_scopes, loop);
                if(replacement!=(*i)->name)
                        replace_map[(*i)->name] = replacement;
        }
@@ -1128,6 +1146,7 @@ ProgramBuilder::StandardFeatures::Loader::Loader(StandardFeatures &f):
        add("clipping",  &StandardFeatures::clipping);
        add("custom",    &StandardFeatures::custom);
        add("fog",       &StandardFeatures::fog);
+       add("geometry",  &StandardFeatures::geometry);
        add("lighting",  &StandardFeatures::lighting);
        add("material",  &StandardFeatures::material);
        add("max_clip_planes", &StandardFeatures::max_clip_planes);

diff --git a/source/programbuilder.h b/source/programbuilder.h
index f2046e458f7e81c650dcd73de36f2fe4b59fa8a7..053eb567487a9a03964235a5d04b3d84c555a68c 100644 (file)
--- a/source/programbuilder.h
+++ b/source/programbuilder.h
@@ -104,6 +104,9 @@ public:
                /** Number of clipping planes to process. */
                unsigned max_clip_planes;
 
+               /** Use a geometry shader. */
+               bool geometry;
+
                /** Force the use of legacy shaders conforming to GLSL 1.10.   Defaults
                to true if the version of GLSL is less than 1.30, false otherwise. */
                bool legacy;
@@ -125,7 +128,9 @@ private:
                UNIFORM,
                ATTRIBUTE,
                VERTEX,
-               FRAGMENT
+               GEOMETRY,
+               FRAGMENT,
+               N_SCOPES
        };
 
        enum InterfaceFlags
@@ -177,8 +182,8 @@ private:
                InterfaceFlags get_interface_flags(VariableScope) const;
                std::string create_type_declaration() const;
                std::string create_declaration(char = 0, bool = false) const;
-               std::string create_replacement(VariableScope, const char * = 0) const;
-               std::string create_expression(const char * = 0) const;
+               std::string create_replacement(VariableScope, unsigned, const char * = 0) const;
+               std::string create_expression(unsigned, const char * = 0) const;
        };
 
        enum MatchType
@@ -192,6 +197,7 @@ private:
        StandardFeatures features;
        std::list<VariableDefinition> custom_variables;
        std::string feature_flags;
+       unsigned enabled_scopes;
        std::map<std::string, std::string> aliases;
        bool optimize;
 
@@ -218,6 +224,7 @@ private:
        static bool parse_identifier(const char *, unsigned &, unsigned &);
        static std::vector<std::string> extract_identifiers(const char *);
        static std::string replace_identifiers(const char *, const std::map<std::string, std::string> &, bool = false);
+       static VariableScope previous_scope(VariableScope, unsigned);
        std::string create_expression(const ShaderVariable &, const char * = 0) const;
 };