[Feat] (MG_State, MG_Impl): give program pipelines their object and their state

Every program pipeline entry point was an export stub, and the stub macro's `return (type)1` made glIsProgramPipeline answer GL_TRUE for anything - including the names glGenProgramPipelines had never written. All four direct_state_access.program_pipelines cases failed. ProgramPipelineObject holds what GL 4.6 core 7.4 says a pipeline is: a program reference per shader stage, the active program glProgramUniform* addresses, a validate status and an info log. Its validate status starts false, unlike ProgramObject's, because a pipeline that has never been validated must report GL_VALIDATE_STATUS as 0. The name rules follow the shape queries and transform feedbacks already use, and which the CTS checks first: glGenProgramPipelines only RESERVES a name and glIsProgramPipeline answers GL_FALSE for it; the object appears on first bind, or immediately from glCreateProgramPipelines. Map membership is object existence - a pipeline, unlike a transform feedback, has no stateful default object zero, so no everBound flag is needed. glGet(GL_PROGRAM_PIPELINE_BINDING) reports the real binding now instead of a hardcoded zero whose comment said the entry points were stubbed. This is the state half only. program_pipelines_functional needs mixed-stage rendering - a vertex-only and a fragment-only program drawn together - and stays failing; glCreateShaderProgramv is deliberately left stubbed until that lands, so nothing can half-work in between. Takes program_pipelines_creation, _defaults and _errors from failing to passing on both backends.
2026-09-09 12:48:32 +09:00 · 2026-08-05 05:43:13 -04:00
parent 1f1a331a44
commit 300b458132
8 changed files with 385 additions and 11 deletions
@@ -218,6 +218,7 @@ set(SOURCE_FILES
    MobileGL/MG_Impl/GLImpl/Framebuffer/Validators.cpp
    MobileGL/MG_Impl/GLImpl/Framebuffer/GL_Framebuffer.cpp
    MobileGL/MG_Impl/GLImpl/Program/GL_Program.cpp
+    MobileGL/MG_Impl/GLImpl/Program/GL_ProgramPipeline.cpp
    MobileGL/MG_Impl/GLImpl/Texture/GL_Texture.cpp
    MobileGL/MG_Impl/GLImpl/Texture/Validators.cpp
    MobileGL/MG_Impl/GLImpl/Texture/ProxyTexture.cpp
@@ -15,6 +15,7 @@
 #include "../Texture/GL_Texture.h"
 #include "../Drawing/GL_Drawing.h"
 #include "../Program/GL_Program.h"
+#include "../Program/GL_ProgramPipeline.h"
 #include "../RenderState/GL_RenderState.h"
 #include "../Framebuffer/GL_Framebuffer.h"
 #include "../VertexArray/GL_VertexArray.h"
@@ -317,14 +318,14 @@ DECLARE_GL_FUNCTION_HEAD(GLuint, GetProgramResourceIndex, GLuint program, GLenum
 DECLARE_GL_FUNCTION_HEAD(void, GetProgramResourceName, GLuint program, GLenum programInterface, GLuint index, GLsizei bufSize, GLsizei* length, GLchar* name) DECLARE_GL_FUNCTION_END_NO_RETURN(void, GetProgramResourceName, program, programInterface, index, bufSize, length, name)
 DECLARE_GL_FUNCTION_HEAD(void, GetProgramResourceiv, GLuint program, GLenum programInterface, GLuint index, GLsizei propCount, const GLenum* props, GLsizei bufSize, GLsizei* length, GLint* params) DECLARE_GL_FUNCTION_END_NO_RETURN(void, GetProgramResourceiv, program, programInterface, index, propCount, props, bufSize, length, params)
 DECLARE_GL_FUNCTION_HEAD(GLint, GetProgramResourceLocation, GLuint program, GLenum programInterface, const GLchar* name) DECLARE_GL_FUNCTION_END(GLint, GetProgramResourceLocation, program, programInterface, name)
-DECLARE_GL_FUNCTION_STUB_HEAD(void, UseProgramStages, GLuint pipeline, GLbitfield stages, GLuint program) DECLARE_GL_FUNCTION_STUB_END_NO_RETURN(void, UseProgramStages, pipeline, stages, program)
-DECLARE_GL_FUNCTION_STUB_HEAD(void, ActiveShaderProgram, GLuint pipeline, GLuint program) DECLARE_GL_FUNCTION_STUB_END_NO_RETURN(void, ActiveShaderProgram, pipeline, program)
+DECLARE_GL_FUNCTION_HEAD(void, UseProgramStages, GLuint pipeline, GLbitfield stages, GLuint program) DECLARE_GL_FUNCTION_END_NO_RETURN(void, UseProgramStages, pipeline, stages, program)
+DECLARE_GL_FUNCTION_HEAD(void, ActiveShaderProgram, GLuint pipeline, GLuint program) DECLARE_GL_FUNCTION_END_NO_RETURN(void, ActiveShaderProgram, pipeline, program)
 DECLARE_GL_FUNCTION_STUB_HEAD(GLuint, CreateShaderProgramv, GLenum type, GLsizei count, const GLchar* const* strings) DECLARE_GL_FUNCTION_STUB_END(GLuint, CreateShaderProgramv, type, count, strings)
-DECLARE_GL_FUNCTION_STUB_HEAD(void, BindProgramPipeline, GLuint pipeline) DECLARE_GL_FUNCTION_STUB_END_NO_RETURN(void, BindProgramPipeline, pipeline)
-DECLARE_GL_FUNCTION_STUB_HEAD(void, DeleteProgramPipelines, GLsizei n, const GLuint* pipelines) DECLARE_GL_FUNCTION_STUB_END_NO_RETURN(void, DeleteProgramPipelines, n, pipelines)
-DECLARE_GL_FUNCTION_STUB_HEAD(void, GenProgramPipelines, GLsizei n, GLuint* pipelines) DECLARE_GL_FUNCTION_STUB_END_NO_RETURN(void, GenProgramPipelines, n, pipelines)
-DECLARE_GL_FUNCTION_STUB_HEAD(GLboolean, IsProgramPipeline, GLuint pipeline) DECLARE_GL_FUNCTION_STUB_END(GLboolean, IsProgramPipeline, pipeline)
-DECLARE_GL_FUNCTION_STUB_HEAD(void, GetProgramPipelineiv, GLuint pipeline, GLenum pname, GLint* params) DECLARE_GL_FUNCTION_STUB_END_NO_RETURN(void, GetProgramPipelineiv, pipeline, pname, params)
+DECLARE_GL_FUNCTION_HEAD(void, BindProgramPipeline, GLuint pipeline) DECLARE_GL_FUNCTION_END_NO_RETURN(void, BindProgramPipeline, pipeline)
+DECLARE_GL_FUNCTION_HEAD(void, DeleteProgramPipelines, GLsizei n, const GLuint* pipelines) DECLARE_GL_FUNCTION_END_NO_RETURN(void, DeleteProgramPipelines, n, pipelines)
+DECLARE_GL_FUNCTION_HEAD(void, GenProgramPipelines, GLsizei n, GLuint* pipelines) DECLARE_GL_FUNCTION_END_NO_RETURN(void, GenProgramPipelines, n, pipelines)
+DECLARE_GL_FUNCTION_HEAD(GLboolean, IsProgramPipeline, GLuint pipeline) DECLARE_GL_FUNCTION_END(GLboolean, IsProgramPipeline, pipeline)
+DECLARE_GL_FUNCTION_HEAD(void, GetProgramPipelineiv, GLuint pipeline, GLenum pname, GLint* params) DECLARE_GL_FUNCTION_END_NO_RETURN(void, GetProgramPipelineiv, pipeline, pname, params)
 DECLARE_GL_FUNCTION_HEAD(void, ProgramUniform1i, GLuint program, GLint location, GLint v0) DECLARE_GL_FUNCTION_END_NO_RETURN(void, ProgramUniform1i, program, location, v0)
 DECLARE_GL_FUNCTION_HEAD(void, ProgramUniform2i, GLuint program, GLint location, GLint v0, GLint v1) DECLARE_GL_FUNCTION_END_NO_RETURN(void, ProgramUniform2i, program, location, v0, v1)
 DECLARE_GL_FUNCTION_HEAD(void, ProgramUniform3i, GLuint program, GLint location, GLint v0, GLint v1, GLint v2) DECLARE_GL_FUNCTION_END_NO_RETURN(void, ProgramUniform3i, program, location, v0, v1, v2)
@@ -358,8 +359,8 @@ DECLARE_GL_FUNCTION_HEAD(void, ProgramUniformMatrix2x4fv, GLuint program, GLint
 DECLARE_GL_FUNCTION_HEAD(void, ProgramUniformMatrix4x2fv, GLuint program, GLint location, GLsizei count, GLboolean transpose, const GLfloat* value) DECLARE_GL_FUNCTION_END_NO_RETURN(void, ProgramUniformMatrix4x2fv, program, location, count, transpose, value)
 DECLARE_GL_FUNCTION_HEAD(void, ProgramUniformMatrix3x4fv, GLuint program, GLint location, GLsizei count, GLboolean transpose, const GLfloat* value) DECLARE_GL_FUNCTION_END_NO_RETURN(void, ProgramUniformMatrix3x4fv, program, location, count, transpose, value)
 DECLARE_GL_FUNCTION_HEAD(void, ProgramUniformMatrix4x3fv, GLuint program, GLint location, GLsizei count, GLboolean transpose, const GLfloat* value) DECLARE_GL_FUNCTION_END_NO_RETURN(void, ProgramUniformMatrix4x3fv, program, location, count, transpose, value)
-DECLARE_GL_FUNCTION_STUB_HEAD(void, ValidateProgramPipeline, GLuint pipeline) DECLARE_GL_FUNCTION_STUB_END_NO_RETURN(void, ValidateProgramPipeline, pipeline)
-DECLARE_GL_FUNCTION_STUB_HEAD(void, GetProgramPipelineInfoLog, GLuint pipeline, GLsizei bufSize, GLsizei* length, GLchar* infoLog) DECLARE_GL_FUNCTION_STUB_END_NO_RETURN(void, GetProgramPipelineInfoLog, pipeline, bufSize, length, infoLog)
+DECLARE_GL_FUNCTION_HEAD(void, ValidateProgramPipeline, GLuint pipeline) DECLARE_GL_FUNCTION_END_NO_RETURN(void, ValidateProgramPipeline, pipeline)
+DECLARE_GL_FUNCTION_HEAD(void, GetProgramPipelineInfoLog, GLuint pipeline, GLsizei bufSize, GLsizei* length, GLchar* infoLog) DECLARE_GL_FUNCTION_END_NO_RETURN(void, GetProgramPipelineInfoLog, pipeline, bufSize, length, infoLog)
 DECLARE_GL_FUNCTION_HEAD(void, BindImageTexture, GLuint unit, GLuint texture, GLint level, GLboolean layered, GLint layer, GLenum access, GLenum format) DECLARE_GL_FUNCTION_END_NO_RETURN(void, BindImageTexture, unit, texture, level, layered, layer, access, format)
 DECLARE_GL_FUNCTION_HEAD(void, GetBooleani_v, GLenum target, GLuint index, GLboolean* data) DECLARE_GL_FUNCTION_END_NO_RETURN(void, GetBooleani_v, target, index, data)
 DECLARE_GL_FUNCTION_HEAD(void, MemoryBarrier, GLbitfield barriers) DECLARE_GL_FUNCTION_END_NO_RETURN(void, MemoryBarrier, barriers)
@@ -1096,7 +1097,7 @@ DECLARE_GL_FUNCTION_HEAD(void, GetVertexArrayiv, GLuint vaobj, GLenum pname, GLi
 DECLARE_GL_FUNCTION_HEAD(void, GetVertexArrayIndexediv, GLuint vaobj, GLuint index, GLenum pname, GLint* param) DECLARE_GL_FUNCTION_END_NO_RETURN(void, GetVertexArrayIndexediv, vaobj, index, pname, param)
 DECLARE_GL_FUNCTION_HEAD(void, GetVertexArrayIndexed64iv, GLuint vaobj, GLuint index, GLenum pname, GLint64* param) DECLARE_GL_FUNCTION_END_NO_RETURN(void, GetVertexArrayIndexed64iv, vaobj, index, pname, param)
 DECLARE_GL_FUNCTION_HEAD(void, CreateSamplers, GLsizei n, GLuint* samplers) DECLARE_GL_FUNCTION_END_NO_RETURN(void, CreateSamplers, n, samplers)
-DECLARE_GL_FUNCTION_STUB_HEAD(void, CreateProgramPipelines, GLsizei n, GLuint* pipelines) DECLARE_GL_FUNCTION_STUB_END_NO_RETURN(void, CreateProgramPipelines, n, pipelines)
+DECLARE_GL_FUNCTION_HEAD(void, CreateProgramPipelines, GLsizei n, GLuint* pipelines) DECLARE_GL_FUNCTION_END_NO_RETURN(void, CreateProgramPipelines, n, pipelines)
 DECLARE_GL_FUNCTION_HEAD(void, CreateQueries, GLenum target, GLsizei n, GLuint* ids) DECLARE_GL_FUNCTION_END_NO_RETURN(void, CreateQueries, target, n, ids)
 DECLARE_GL_FUNCTION_HEAD(void, GetQueryBufferObjecti64v, GLuint id, GLuint buffer, GLenum pname, GLintptr offset) DECLARE_GL_FUNCTION_END_NO_RETURN(void, GetQueryBufferObjecti64v, id, buffer, pname, offset)
 DECLARE_GL_FUNCTION_HEAD(void, GetQueryBufferObjectiv, GLuint id, GLuint buffer, GLenum pname, GLintptr offset) DECLARE_GL_FUNCTION_END_NO_RETURN(void, GetQueryBufferObjectiv, id, buffer, pname, offset)
@@ -1432,7 +1432,7 @@ namespace MobileGL::MG_Impl::GLImpl {
            *params = 0; // program-binary entrypoints are stubbed
            return;
        case GL_PROGRAM_PIPELINE_BINDING:
-            *params = 0; // program-pipeline entrypoints are stubbed
+            *params = static_cast<GLint>(MG_State::pGLContext->GetBoundProgramPipelineName());
            return;
        case GL_PROGRAM_POINT_SIZE:
            *params = MG_State::pGLContext->IsCapabilityEnabled(CapabilityInput::ProgramPointSize) ? GL_TRUE : GL_FALSE;
@@ -0,0 +1,231 @@
+// MobileGL - MobileGL/MG_Impl/GLImpl/Program/GL_ProgramPipeline.cpp
+// Copyright (c) 2025-2026 MobileGL-Dev
+// Licensed under the GNU Lesser General Public License v3.0:
+//   https://www.gnu.org/licenses/gpl-3.0.txt
+//   https://www.gnu.org/licenses/lgpl-3.0.txt
+// SPDX-License-Identifier: LGPL-3.0-only
+// End of Source File Header
+
+#include "GL_ProgramPipeline.h"
+
+#include <MG_State/GLState/Core.h>
+#include <MG_State/GLState/ErrorState/ErrorInfo.h>
+#include <MG_Util/Converters/GLToStr/GLEnumConverter.h>
+
+namespace MobileGL::MG_Impl::GLImpl {
+    namespace {
+        void RecordPipelineError(ErrorCode code, const char* function, String message) {
+            MG_State::pGLContext->RecordError(
+                code, MakeUnique<GenericErrorInfo>("MG_Impl/GLImpl", function, Move(message)));
+        }
+
+        // A pipeline name only names an object once it has been bound or created; querying a
+        // reserved-but-unmaterialised name is INVALID_OPERATION (GL 4.6 core 7.4).
+        const SharedPtr<MG_State::GLState::ProgramPipelineObject>* TryGetPipeline(GLuint pipeline,
+                                                                                 const char* function) {
+            if (!MG_State::pGLContext->IsProgramPipelineObject(pipeline)) {
+                RecordPipelineError(ErrorCode::InvalidOperation, function,
+                                    std::format("Program pipeline {} does not exist.", pipeline));
+                return nullptr;
+            }
+            return &MG_State::pGLContext->GetProgramPipelineObject(pipeline);
+        }
+
+        Bool ValidatePipelineCount(GLsizei n, const char* function) {
+            if (n < 0) {
+                RecordPipelineError(ErrorCode::InvalidValue, function, "n must be non-negative.");
+                return false;
+            }
+            return true;
+        }
+
+        // GL 4.6 core table 7.1 maps each stage bit onto a shader stage.
+        Bool TryResolveStageBit(GLbitfield bit, ShaderStage& outStage) {
+            switch (bit) {
+            case GL_VERTEX_SHADER_BIT: outStage = ShaderStage::Vertex; return true;
+            case GL_TESS_CONTROL_SHADER_BIT: outStage = ShaderStage::TessControl; return true;
+            case GL_TESS_EVALUATION_SHADER_BIT: outStage = ShaderStage::TessEval; return true;
+            case GL_GEOMETRY_SHADER_BIT: outStage = ShaderStage::Geometry; return true;
+            case GL_FRAGMENT_SHADER_BIT: outStage = ShaderStage::Fragment; return true;
+            case GL_COMPUTE_SHADER_BIT: outStage = ShaderStage::Compute; return true;
+            default: return false;
+            }
+        }
+
+        constexpr GLbitfield kAllStageBits = GL_VERTEX_SHADER_BIT | GL_TESS_CONTROL_SHADER_BIT |
+                                            GL_TESS_EVALUATION_SHADER_BIT | GL_GEOMETRY_SHADER_BIT |
+                                            GL_FRAGMENT_SHADER_BIT | GL_COMPUTE_SHADER_BIT;
+    } // namespace
+
+    void GenProgramPipelines(GLsizei n, GLuint* pipelines) {
+        if (!ValidatePipelineCount(n, __func__)) return;
+        if (n == 0 || !pipelines) return;
+
+        static thread_local Vector<GLuint> names;
+        MG_State::pGLContext->GenProgramPipelineNames(static_cast<Uint>(n), names);
+        Memcpy(pipelines, names.data(), static_cast<SizeT>(n) * sizeof(GLuint));
+    }
+
+    void CreateProgramPipelines(GLsizei n, GLuint* pipelines) {
+        if (!ValidatePipelineCount(n, __func__)) return;
+        if (n == 0 || !pipelines) return;
+
+        static thread_local Vector<GLuint> names;
+        MG_State::pGLContext->GenProgramPipelineNames(static_cast<Uint>(n), names);
+        for (GLsizei i = 0; i < n; ++i) {
+            pipelines[i] = names[static_cast<SizeT>(i)];
+            MG_State::pGLContext->CreateProgramPipelineObject(names[static_cast<SizeT>(i)]);
+        }
+    }
+
+    void DeleteProgramPipelines(GLsizei n, const GLuint* pipelines) {
+        if (!ValidatePipelineCount(n, __func__)) return;
+        if (!pipelines) return;
+
+        for (GLsizei i = 0; i < n; ++i) {
+            // Deleting zero, an unknown name, or a name that was only reserved is silently ignored.
+            MG_State::pGLContext->MarkProgramPipelineForDeletion(pipelines[i]);
+        }
+    }
+
+    void BindProgramPipeline(GLuint pipeline) {
+        if (pipeline != 0 && !MG_State::pGLContext->ValidateProgramPipelineName(pipeline)) {
+            RecordPipelineError(ErrorCode::InvalidOperation, __func__,
+                                std::format("Program pipeline name {} is not valid.", pipeline));
+            return;
+        }
+        MG_State::pGLContext->BindProgramPipelineObject(pipeline);
+    }
+
+    GLboolean IsProgramPipeline(GLuint pipeline) {
+        return MG_State::pGLContext->IsProgramPipelineObject(pipeline) ? GL_TRUE : GL_FALSE;
+    }
+
+    void GetProgramPipelineiv(GLuint pipeline, GLenum pname, GLint* params) {
+        const auto* pipelineObject = TryGetPipeline(pipeline, __func__);
+        if (!pipelineObject || !params) return;
+
+        const auto stageProgramName = [&](ShaderStage stage) -> GLint {
+            const auto& program = (*pipelineObject)->GetStageProgram(stage);
+            return program ? static_cast<GLint>(program->GetExternalIndex()) : 0;
+        };
+
+        switch (pname) {
+        case GL_ACTIVE_PROGRAM: {
+            const auto& active = (*pipelineObject)->GetActiveProgram();
+            *params = active ? static_cast<GLint>(active->GetExternalIndex()) : 0;
+            break;
+        }
+        case GL_VERTEX_SHADER: *params = stageProgramName(ShaderStage::Vertex); break;
+        case GL_TESS_CONTROL_SHADER: *params = stageProgramName(ShaderStage::TessControl); break;
+        case GL_TESS_EVALUATION_SHADER: *params = stageProgramName(ShaderStage::TessEval); break;
+        case GL_GEOMETRY_SHADER: *params = stageProgramName(ShaderStage::Geometry); break;
+        case GL_FRAGMENT_SHADER: *params = stageProgramName(ShaderStage::Fragment); break;
+        case GL_COMPUTE_SHADER: *params = stageProgramName(ShaderStage::Compute); break;
+        case GL_VALIDATE_STATUS: *params = (*pipelineObject)->GetValidateStatus() ? GL_TRUE : GL_FALSE; break;
+        case GL_INFO_LOG_LENGTH: {
+            // GL counts the null terminator, and reports 0 rather than 1 for an empty log.
+            const auto& log = (*pipelineObject)->GetInfoLog();
+            *params = log.empty() ? 0 : static_cast<GLint>(log.length()) + 1;
+            break;
+        }
+        default:
+            RecordPipelineError(ErrorCode::InvalidEnum, __func__,
+                                std::format("pname {} is not a program pipeline parameter.",
+                                            MG_Util::ConvertGLEnumToString(pname)));
+            break;
+        }
+    }
+
+    void GetProgramPipelineInfoLog(GLuint pipeline, GLsizei bufSize, GLsizei* length, GLchar* infoLog) {
+        const auto* pipelineObject = TryGetPipeline(pipeline, __func__);
+        if (!pipelineObject) return;
+        if (bufSize < 0) {
+            RecordPipelineError(ErrorCode::InvalidValue, __func__, "bufSize must be non-negative.");
+            return;
+        }
+        if (bufSize == 0 || !infoLog) {
+            if (length) *length = 0;
+            return;
+        }
+
+        const auto& log = (*pipelineObject)->GetInfoLog();
+        const auto copied = std::min<GLsizei>(bufSize - 1, static_cast<GLsizei>(log.length()));
+        if (copied > 0) Memcpy(infoLog, log.data(), static_cast<SizeT>(copied));
+        infoLog[copied] = '\0';
+        if (length) *length = copied;
+    }
+
+    void UseProgramStages(GLuint pipeline, GLbitfield stages, GLuint program) {
+        if (stages != GL_ALL_SHADER_BITS && (stages & ~kAllStageBits) != 0) {
+            RecordPipelineError(ErrorCode::InvalidValue, __func__, "stages names a bit that is not a shader stage.");
+            return;
+        }
+        const auto* pipelineObject = TryGetPipeline(pipeline, __func__);
+        if (!pipelineObject) return;
+
+        SharedPtr<MG_State::GLState::ProgramObject> programObject;
+        if (program != 0) {
+            if (!MG_State::pGLContext->ValidateProgramName(program)) {
+                RecordPipelineError(ErrorCode::InvalidValue, __func__,
+                                    std::format("{} is not the name of a program object.", program));
+                return;
+            }
+            programObject = MG_State::pGLContext->GetProgramObject(program);
+            if (!programObject) {
+                RecordPipelineError(ErrorCode::InvalidValue, __func__,
+                                    std::format("{} is not the name of a program object.", program));
+                return;
+            }
+            if (!programObject->GetLinkStatus()) {
+                RecordPipelineError(ErrorCode::InvalidOperation, __func__,
+                                    std::format("Program {} has not been linked successfully.", program));
+                return;
+            }
+        }
+
+        const GLbitfield selected = stages == GL_ALL_SHADER_BITS ? kAllStageBits : stages;
+        for (GLbitfield bit = 1; bit != 0 && bit <= kAllStageBits; bit <<= 1) {
+            if ((selected & bit) == 0) continue;
+            ShaderStage stage = ShaderStage::Unknown;
+            if (!TryResolveStageBit(bit, stage)) continue;
+            // program == 0 clears the stage, which is what a null program reference means here.
+            (*pipelineObject)->SetStageProgram(stage, programObject);
+        }
+    }
+
+    void ActiveShaderProgram(GLuint pipeline, GLuint program) {
+        const auto* pipelineObject = TryGetPipeline(pipeline, __func__);
+        if (!pipelineObject) return;
+
+        if (program == 0) {
+            (*pipelineObject)->SetActiveProgram(nullptr);
+            return;
+        }
+        if (!MG_State::pGLContext->ValidateProgramName(program)) {
+            RecordPipelineError(ErrorCode::InvalidValue, __func__,
+                                std::format("{} is not the name of a program object.", program));
+            return;
+        }
+        auto programObject = MG_State::pGLContext->GetProgramObject(program);
+        if (!programObject) {
+            RecordPipelineError(ErrorCode::InvalidValue, __func__,
+                                std::format("{} is not the name of a program object.", program));
+            return;
+        }
+        if (!programObject->GetLinkStatus()) {
+            RecordPipelineError(ErrorCode::InvalidOperation, __func__,
+                                std::format("Program {} has not been linked successfully.", program));
+            return;
+        }
+        (*pipelineObject)->SetActiveProgram(programObject);
+    }
+
+    void ValidateProgramPipeline(GLuint pipeline) {
+        const auto* pipelineObject = TryGetPipeline(pipeline, __func__);
+        if (!pipelineObject) return;
+        // Nothing here can fail today: MobileGL links each stage program on its own, so there is no
+        // cross-stage interface to re-check at validation time. The log stays empty, which GL allows.
+        (*pipelineObject)->SetValidateStatus(true);
+    }
+} // namespace MobileGL::MG_Impl::GLImpl
@@ -0,0 +1,23 @@
+// MobileGL - MobileGL/MG_Impl/GLImpl/Program/GL_ProgramPipeline.h
+// Copyright (c) 2025-2026 MobileGL-Dev
+// Licensed under the GNU Lesser General Public License v3.0:
+//   https://www.gnu.org/licenses/gpl-3.0.txt
+//   https://www.gnu.org/licenses/lgpl-3.0.txt
+// SPDX-License-Identifier: LGPL-3.0-only
+// End of Source File Header
+
+#pragma once
+#include <Includes.h>
+
+namespace MobileGL::MG_Impl::GLImpl {
+    void GenProgramPipelines(GLsizei n, GLuint* pipelines);
+    void CreateProgramPipelines(GLsizei n, GLuint* pipelines);
+    void DeleteProgramPipelines(GLsizei n, const GLuint* pipelines);
+    void BindProgramPipeline(GLuint pipeline);
+    GLboolean IsProgramPipeline(GLuint pipeline);
+    void GetProgramPipelineiv(GLuint pipeline, GLenum pname, GLint* params);
+    void GetProgramPipelineInfoLog(GLuint pipeline, GLsizei bufSize, GLsizei* length, GLchar* infoLog);
+    void UseProgramStages(GLuint pipeline, GLbitfield stages, GLuint program);
+    void ActiveShaderProgram(GLuint pipeline, GLuint program);
+    void ValidateProgramPipeline(GLuint pipeline);
+} // namespace MobileGL::MG_Impl::GLImpl
@@ -802,6 +802,53 @@ namespace MobileGL::MG_State {
                m_transformFeedbackObjects[id] = {};
            }
        }
+        // Program pipeline
+        void GLContext::GenProgramPipelineNames(Uint number, Vector<Uint>& pipelines) {
+            pipelines.resize(number);
+            // Names only: glIsProgramPipeline must answer GL_FALSE until one is bound or created.
+            m_programPipelineNames.Generate(number, pipelines.data());
+        }
+
+        void GLContext::CreateProgramPipelineObject(Uint index) {
+            m_programPipelines[index] = MakeShared<ProgramPipelineObject>(index);
+        }
+
+        Bool GLContext::ValidateProgramPipelineName(Uint index) const {
+            return index == 0 || m_programPipelineNames.IsValid(index);
+        }
+
+        Bool GLContext::IsProgramPipelineObject(Uint index) const {
+            if (index == 0 || !m_programPipelineNames.IsValid(index)) return false;
+            return m_programPipelines.find(index) != m_programPipelines.end();
+        }
+
+        void GLContext::BindProgramPipelineObject(Uint index) {
+            if (index != 0 && m_programPipelines.find(index) == m_programPipelines.end()) {
+                // First bind is what turns a reserved name into an object.
+                m_programPipelines[index] = MakeShared<ProgramPipelineObject>(index);
+            }
+            m_boundProgramPipeline = index;
+        }
+
+        void GLContext::MarkProgramPipelineForDeletion(Uint index) {
+            if (index == 0 || !m_programPipelineNames.IsValid(index)) return;
+            if (index == m_boundProgramPipeline) {
+                m_boundProgramPipeline = 0;
+            }
+            m_programPipelines.erase(index);
+            m_programPipelineNames.Delete(index);
+        }
+
+        const SharedPtr<ProgramPipelineObject>& GLContext::GetProgramPipelineObject(Uint index) const {
+            static const SharedPtr<ProgramPipelineObject> kNone;
+            const auto it = m_programPipelines.find(index);
+            return it == m_programPipelines.end() ? kNone : it->second;
+        }
+
+        const SharedPtr<ProgramPipelineObject>& GLContext::GetBoundProgramPipeline() const {
+            return GetProgramPipelineObject(m_boundProgramPipeline);
+        }
+

        Bool GLContext::ValidateTransformFeedbackName(Uint index) const {
            return index == 0 || m_transformFeedbackNames.IsValid(index);
@@ -14,6 +14,7 @@
 #include "MG_State/GLState/RenderbufferState/RenderbufferState.h"
 #include "RenderState/RenderState.h"
 #include "ProgramState/ProgramState.h"
+#include "ProgramState/ProgramPipelineObject.h"
 #include "SamplerState/SamplerState.h"
 #include "TextureState/TextureState.h"
 #include "FramebufferState/FramebufferState.h"
@@ -137,6 +138,19 @@ namespace MobileGL {
                void UseProgram(Uint program);
                const SharedPtr<ProgramObject>& GetCurrentProgram();

+                // Program pipeline (GL_ARB_separate_shader_objects, GL 4.6 core 7.4). Like queries
+                // and transform feedbacks, glGenProgramPipelines only RESERVES a name - the object
+                // appears on first bind - while glCreateProgramPipelines makes it immediately.
+                void GenProgramPipelineNames(Uint number, Vector<Uint>& pipelines);
+                void CreateProgramPipelineObject(Uint index);
+                Bool ValidateProgramPipelineName(Uint index) const;
+                Bool IsProgramPipelineObject(Uint index) const;
+                void BindProgramPipelineObject(Uint index);
+                void MarkProgramPipelineForDeletion(Uint index);
+                const SharedPtr<ProgramPipelineObject>& GetProgramPipelineObject(Uint index) const;
+                Uint GetBoundProgramPipelineName() const { return m_boundProgramPipeline; }
+                const SharedPtr<ProgramPipelineObject>& GetBoundProgramPipeline() const;
+
                // RenderState
                Uint GetRenderStateParametersVersion() const;
                const RenderStateParameters& GetRenderStateParameters() const;
@@ -390,6 +404,11 @@ namespace MobileGL {
                UnorderedMap<Uint, TransformFeedbackObjectState> m_transformFeedbackObjects;
                IndexGenerator<Uint> m_transformFeedbackNames;
                Uint m_boundTransformFeedback = 0;
+                // Map membership IS object existence here: a pipeline has no stateful default
+                // object 0, so no everBound flag is needed.
+                UnorderedMap<Uint, SharedPtr<ProgramPipelineObject>> m_programPipelines;
+                IndexGenerator<Uint> m_programPipelineNames;
+                Uint m_boundProgramPipeline = 0;
                TextureState m_textureState;
                ProgramState m_programState;
                RenderState m_renderState;
@@ -0,0 +1,52 @@
+// MobileGL - MobileGL/MG_State/GLState/ProgramState/ProgramPipelineObject.h
+// Copyright (c) 2025-2026 MobileGL-Dev
+// Licensed under the GNU Lesser General Public License v3.0:
+//   https://www.gnu.org/licenses/gpl-3.0.txt
+//   https://www.gnu.org/licenses/lgpl-3.0.txt
+// SPDX-License-Identifier: LGPL-3.0-only
+// End of Source File Header
+
+#pragma once
+#include <Includes.h>
+#include "ProgramObject.h"
+
+namespace MobileGL {
+    namespace MG_State {
+        namespace GLState {
+            // A GL_ARB_separate_shader_objects program pipeline (GL 4.6 core 7.4): a set of
+            // per-stage program references plus the program glProgramUniform* addresses when no
+            // program object is in use.
+            class ProgramPipelineObject {
+            public:
+                explicit ProgramPipelineObject(Uint externalIndex) : m_externalIndex(externalIndex) {}
+
+                const SharedPtr<ProgramObject>& GetStageProgram(ShaderStage stage) const {
+                    return m_stagePrograms[static_cast<SizeT>(stage)];
+                }
+                void SetStageProgram(ShaderStage stage, const SharedPtr<ProgramObject>& program) {
+                    m_stagePrograms[static_cast<SizeT>(stage)] = program;
+                }
+
+                const SharedPtr<ProgramObject>& GetActiveProgram() const { return m_activeProgram; }
+                void SetActiveProgram(const SharedPtr<ProgramObject>& program) { m_activeProgram = program; }
+
+                // Distinct from ProgramObject's, which starts true: a pipeline that has never been
+                // validated must report GL_VALIDATE_STATUS as 0 (GL 4.6 core table 23.31).
+                Bool GetValidateStatus() const { return m_validateStatus; }
+                void SetValidateStatus(Bool value) { m_validateStatus = value; }
+
+                const String& GetInfoLog() const { return m_infoLog; }
+                void SetInfoLog(String log) { m_infoLog = Move(log); }
+
+                Uint GetExternalIndex() const { return m_externalIndex; }
+
+            private:
+                Array<SharedPtr<ProgramObject>, static_cast<SizeT>(ShaderStage::ShaderStageCount)> m_stagePrograms{};
+                SharedPtr<ProgramObject> m_activeProgram;
+                String m_infoLog;
+                const Uint m_externalIndex = 0;
+                Bool m_validateStatus = false;
+            };
+        } // namespace GLState
+    } // namespace MG_State
+} // namespace MobileGL