Use a #pragma as shader stage delimiter

The special comment was a bad idea with poorly defined semantics.

diff --git a/shaderlib/ambientocclusion.glsl b/shaderlib/ambientocclusion.glsl
index 286072c03813d420f1be5970ca91034be236c04c..7f1e79a019a290c8b341f95970d6226e6eecb475 100644 (file)
--- a/shaderlib/ambientocclusion.glsl
+++ b/shaderlib/ambientocclusion.glsl
@@ -14,7 +14,7 @@ uniform AmbientOcclusionParams
        float occlusion_radius;
 };
 
-////// fragment
+#pragma MSP stage(fragment)
 vec3 project(vec3 position)
 {
        vec4 pp = projection_matrix*vec4(position, 1.0);

diff --git a/shaderlib/ambientocclusion_combine.glsl b/shaderlib/ambientocclusion_combine.glsl
index f56bddbc520809cc37ca6ae8d0ca7753751907d6..1e8bd821d48d1fa4b2ad749dd19bd4ad0b01d6ec 100644 (file)
--- a/shaderlib/ambientocclusion_combine.glsl
+++ b/shaderlib/ambientocclusion_combine.glsl
@@ -1,7 +1,7 @@
 import postprocess;
 import ambientocclusion;
 
-////// fragment
+#pragma MSP stage(fragment)
 void main()
 {
        vec3 center = unproject(vec3(vertex.xy, texture(depth, texcoord).r));

diff --git a/shaderlib/ambientocclusion_occlude.glsl b/shaderlib/ambientocclusion_occlude.glsl
index 6d04d43846cd9b378b211cc88795e819ce1745f3..2a10bde34613cb9cd933c2caa437c6cc781ff162 100644 (file)
--- a/shaderlib/ambientocclusion_occlude.glsl
+++ b/shaderlib/ambientocclusion_occlude.glsl
@@ -1,7 +1,7 @@
 import postprocess;
 import ambientocclusion;
 
-////// fragment
+#pragma MSP stage(fragment)
 void main()
 {
        vec4 rv = texture(rotate, gl_FragCoord.xy/4.0)*2.0-1.0;

diff --git a/shaderlib/bloom_blur.glsl b/shaderlib/bloom_blur.glsl
index 958a53018b50b63bc9ea7d80245e29abf4a8d4ea..aadde901632ef2d60bd2b9e1855d13d308642dba 100644 (file)
--- a/shaderlib/bloom_blur.glsl
+++ b/shaderlib/bloom_blur.glsl
@@ -1,7 +1,7 @@
 import postprocess;
 import bloom;
 
-////// fragment
+#pragma MSP stage(fragment)
 void main()
 {
        frag_color = vec4(0.0, 0.0, 0.0, 0.0);

diff --git a/shaderlib/bloom_combine.glsl b/shaderlib/bloom_combine.glsl
index 4e46776d273d3f4196f0dd9b2c210456cb10bd88..40668636d6d4f4558e198575a38e35c107050727 100644 (file)
--- a/shaderlib/bloom_combine.glsl
+++ b/shaderlib/bloom_combine.glsl
@@ -1,7 +1,7 @@
 import postprocess;
 import bloom;
 
-////// fragment
+#pragma MSP stage(fragment)
 void main()
 {
        frag_color = mix(texture(source, texcoord), texture(blurred, texcoord), strength);

diff --git a/shaderlib/colorcurve.glsl b/shaderlib/colorcurve.glsl
index 63f63138145a2dd73a1d4f82d7542007d3ba90ac..23b5577dc4a05d72cfc46083aa714fd006484938 100644 (file)
--- a/shaderlib/colorcurve.glsl
+++ b/shaderlib/colorcurve.glsl
@@ -7,7 +7,7 @@ uniform ToneMapping
        vec3 brightness_response;
 };
 
-////// fragment
+#pragma MSP stage(fragment)
 void main()
 {
        vec4 incoming = texture(source, texcoord);

diff --git a/shaderlib/postprocess.glsl b/shaderlib/postprocess.glsl
index ff395cdec52193ab4cc73f48350b871094db7bbc..0e632037f3bc148d904eb0fca3bf2e20f93ecb2c 100644 (file)
--- a/shaderlib/postprocess.glsl
+++ b/shaderlib/postprocess.glsl
@@ -1,6 +1,6 @@
 uniform sampler2D source;
 
-////// vertex
+#pragma MSP stage(vertex)
 in vec4 vertex;
 void main()
 {
@@ -9,5 +9,5 @@ void main()
        passthrough;
 }
 
-////// fragment
+#pragma MSP stage(fragment)
 out vec4 frag_color;

diff --git a/shaderlib/singlepass.glsl b/shaderlib/singlepass.glsl
index a80ca339147c028f3200fcbd2e8a2d792819f187..50c3841f3b267afa665a869424030677cbe98dc8 100644 (file)
--- a/shaderlib/singlepass.glsl
+++ b/shaderlib/singlepass.glsl
@@ -76,7 +76,7 @@ uniform Clipping
        ClipPlane clip_planes[max_clip_planes];
 };
 
-////// vertex
+#pragma MSP stage(vertex)
 layout(location=0) in vec4 vertex;
 layout(location=8) in vec4 texcoord;
 layout(location=3) in vec4 color;
@@ -127,7 +127,7 @@ void main()
        passthrough;
 }
 
-////// fragment
+#pragma MSP stage(fragment)
 layout(location=0) out vec4 frag_color;
 
 vec4 get_diffuse_sample()

diff --git a/source/programcompiler.cpp b/source/programcompiler.cpp
index 2dabd7cd8203ff0910eb97c2528e354e0b3943ff..425941baff567e454f8d9ce1390e0b93731cfea4 100644 (file)
--- a/source/programcompiler.cpp
+++ b/source/programcompiler.cpp
@@ -13,12 +13,12 @@ using namespace std;
 namespace {
 
 const char builtins_src[] =
-       "////// vertex\n"
+       "#pragma MSP stage(vertex)\n"
        "out gl_PerVertex {\n"
        "  vec4 gl_Position;\n"
        "  float gl_ClipDistance[];\n"
-       "};"
-       "////// geometry\n"
+       "};\n"
+       "#pragma MSP stage(geometry)\n"
        "in gl_PerVertex {\n"
        "  vec4 gl_Position;\n"
        "  float gl_ClipDistance[];\n"

diff --git a/source/programparser.cpp b/source/programparser.cpp
index c3049dd3649bc5b2d3360b5afa7a4c571787d45c..e7343547da1f5f736da555d68a1f4edeeef76a42 100644 (file)
--- a/source/programparser.cpp
+++ b/source/programparser.cpp
@@ -1,3 +1,4 @@
+#include <msp/core/raii.h>
 #include <msp/strings/format.h>
 #include <msp/strings/regex.h>
 #include "programparser.h"
@@ -91,35 +92,26 @@ Module &ProgramParser::parse(IO::Base &io, const string &n)
 
 void ProgramParser::parse_source()
 {
-       delete module;
-       module = new Module;
-       cur_stage = &module->shared;
-       iter = source.begin();
-       current_line = 1;
        while(1)
        {
-               while(RefPtr<Node> statement = parse_global_declaration())
-                       cur_stage->content.body.push_back(statement);
-
-               parse_token();
-               string token = parse_token();
-               if(token.empty())
+               string::size_type slashes = source.find("//////");
+               if(slashes==string::npos)
                        break;
-               else if(token=="vertex")
-                       module->stages.push_back(VERTEX);
-               else if(token=="geometry")
-                       module->stages.push_back(GEOMETRY);
-               else if(token=="fragment")
-                       module->stages.push_back(FRAGMENT);
-               else
-                       throw runtime_error(format("Parse error at '%s': expected stage identifier", token));
-
-               if(cur_stage->type!=SHARED)
-                       module->stages.back().previous = cur_stage;
-               cur_stage = &module->stages.back();
 
-               for(; (iter!=source.end() && *iter!='\n'); ++iter) ;
+               string::size_type newline = source.find('\n', slashes);
+               string pragma = format("#pragma MSP stage(%s)", source.substr(slashes+6, newline-slashes-6));
+               source.replace(slashes, newline-slashes, pragma);
        }
+
+       delete module;
+       module = new Module;
+       cur_stage = &module->shared;
+       iter = source.begin();
+       source_end = source.end();
+       current_line = 1;
+       allow_preprocess = true;
+       while(RefPtr<Node> statement = parse_global_declaration())
+               cur_stage->content.body.push_back(statement);
 }
 
 string ProgramParser::format_error(const std::string &message)
@@ -154,21 +146,30 @@ const string &ProgramParser::parse_token()
 
 string ProgramParser::parse_token_()
 {
-       if(!skip_comment_and_whitespace())
-               return string();
-
-       if(isalpha(*iter) || *iter=='_')
-               return parse_identifier();
-       else if(isdigit(*iter))
-               return parse_number();
-       else
-               return parse_other();
+       while(1)
+       {
+               skip_comment_and_whitespace();
+               if(iter==source_end)
+                       return string();
+               else if(allow_preprocess && *iter=='#')
+               {
+                       allow_preprocess = false;
+                       SetForScope<deque<string> > clear_tokens(next_tokens, deque<string>());
+                       preprocess();
+               }
+               else if(isalpha(*iter) || *iter=='_')
+                       return parse_identifier();
+               else if(isdigit(*iter))
+                       return parse_number();
+               else
+                       return parse_other();
+       }
 }
 
 string ProgramParser::parse_identifier()
 {
        string ident;
-       while(iter!=source.end())
+       while(iter!=source_end)
        {
                if(isalnum(*iter) || *iter=='_')
                        ident += *iter++;
@@ -183,7 +184,7 @@ string ProgramParser::parse_number()
 {
        bool accept_sign = false;
        string number;
-       while(iter!=source.end())
+       while(iter!=source_end)
        {
                if(isdigit(*iter) || *iter=='.')
                        number += *iter++;
@@ -203,11 +204,11 @@ string ProgramParser::parse_number()
 
 string ProgramParser::parse_other()
 {
-       if(iter==source.end())
+       if(iter==source_end)
                return string();
 
        string token(1, *iter++);
-       for(unsigned i=1; (i<3 && iter!=source.end()); ++i)
+       for(unsigned i=1; (i<3 && iter!=source_end); ++i)
        {
                bool matched = false;
                for(const Operator *j=operators; (!matched && j->type); ++j)
@@ -226,11 +227,10 @@ string ProgramParser::parse_other()
        return token;
 }
 
-bool ProgramParser::skip_comment_and_whitespace()
+void ProgramParser::skip_comment_and_whitespace()
 {
        unsigned comment = 0;
-       unsigned slashes = 0;
-       while(iter!=source.end())
+       while(iter!=source_end)
        {
                if(comment==0)
                {
@@ -242,10 +242,7 @@ bool ProgramParser::skip_comment_and_whitespace()
                else if(comment==1)
                {
                        if(*iter=='/')
-                       {
                                comment = 2;
-                               slashes = 2;
-                       }
                        else if(*iter=='*')
                                comment = 3;
                        else
@@ -259,10 +256,6 @@ bool ProgramParser::skip_comment_and_whitespace()
                {
                        if(*iter=='\n')
                                comment = 0;
-                       else if(*iter=='/')
-                               ++slashes;
-                       else if(!isspace(*iter) && slashes>=6)
-                               return false;
                }
                else if(comment==3 && *iter=='*')
                        comment = 4;
@@ -275,12 +268,13 @@ bool ProgramParser::skip_comment_and_whitespace()
                }
 
                if(*iter=='\n')
+               {
                        ++current_line;
+                       allow_preprocess = (comment<3);
+               }
 
                ++iter;
        }
-
-       return iter!=source.end();
 }
 
 void ProgramParser::expect(const string &token)
@@ -351,9 +345,82 @@ bool ProgramParser::is_identifier(const string &token)
        return re.match(token);
 }
 
+void ProgramParser::preprocess()
+{
+       expect("#");
+
+       string::const_iterator line_end = iter;
+       for(; (line_end!=source_end && *line_end!='\n'); ++line_end) ;
+       SetForScope<string::const_iterator> stop_at_line_end(source_end, line_end);
+
+       string token = peek_token();
+       if(token=="pragma")
+               preprocess_pragma();
+       else if(token=="define" || token=="undef" || token=="if" || token=="ifdef" || token=="ifndef" || token=="else" ||
+               token=="elif" || token=="endif" || token=="error" || token=="extension" || token=="version" || token=="line")
+               throw runtime_error(format_error(format("Unsupported preprocessor directive '%s'", token)));
+       else if(!token.empty())
+               throw runtime_error(format_syntax_error("a preprocessor directive"));
+
+       iter = line_end;
+}
+
+void ProgramParser::preprocess_pragma()
+{
+       expect("pragma");
+       string token = parse_token();
+       if(token=="MSP")
+               preprocess_pragma_msp();
+}
+
+void ProgramParser::preprocess_pragma_msp()
+{
+       string token = peek_token();
+       if(token=="stage")
+               preprocess_stage();
+       else
+               throw runtime_error(format_error(format("Unrecognized MSP pragma '%s'", token)));
+
+       token = parse_token();
+       if(!token.empty())
+               throw runtime_error(format_syntax_error("end of line"));
+}
+
+void ProgramParser::preprocess_stage()
+{
+       if(!allow_stage_change)
+               throw runtime_error(format_error("Changing stage not allowed here"));
+
+       expect("stage");
+       expect("(");
+       string token = expect_identifier();
+       StageType stage = SHARED;
+       if(token=="vertex")
+               stage = VERTEX;
+       else if(token=="geometry")
+               stage = GEOMETRY;
+       else if(token=="fragment")
+               stage = FRAGMENT;
+       else
+               throw runtime_error(format_syntax_error("stage identifier"));
+       expect(")");
+
+       if(stage<=cur_stage->type)
+               throw runtime_error(format_error(format("Stage '%s' not allowed here", token)));
+
+       module->stages.push_back(stage);
+
+       if(cur_stage->type!=SHARED)
+               module->stages.back().previous = cur_stage;
+       cur_stage = &module->stages.back();
+}
+
 RefPtr<Node> ProgramParser::parse_global_declaration()
 {
+       allow_stage_change = true;
        string token = peek_token();
+       allow_stage_change = false;
+
        if(token=="import")
                return parse_import();
        else if(token=="precision")

diff --git a/source/programparser.h b/source/programparser.h
index be6da197481aa3d264c7516427b55859e40e04d9..fa37118de262efe46c02ad0c6c13dcdf43b4517c 100644 (file)
--- a/source/programparser.h
+++ b/source/programparser.h
@@ -40,6 +40,9 @@ private:
        std::string source_name;
        unsigned current_line;
        std::string::const_iterator iter;
+       std::string::const_iterator source_end;
+       bool allow_preprocess;
+       bool allow_stage_change;
        std::string last_token;
        std::deque<std::string> next_tokens;
        ProgramSyntax::Module *module;
@@ -67,7 +70,7 @@ private:
        std::string parse_identifier();
        std::string parse_number();
        std::string parse_other();
-       bool skip_comment_and_whitespace();
+       void skip_comment_and_whitespace();
        void expect(const std::string &);
        std::string expect_type();
        std::string expect_identifier();
@@ -81,6 +84,11 @@ private:
        bool is_type(const std::string &);
        bool is_identifier(const std::string &);
 
+       void preprocess();
+       void preprocess_pragma();
+       void preprocess_pragma_msp();
+       void preprocess_stage();
+
        RefPtr<ProgramSyntax::Node> parse_global_declaration();
        RefPtr<ProgramSyntax::Node> parse_statement();
        RefPtr<ProgramSyntax::Import> parse_import();