Qt: Add preprocessor shader step customization

CHANGES

@@ -5,6 +5,7 @@ Features:
  - Booting of multiboot images
  - Customization of GIF recording
  - Libretro: Cheat code support
+ - Support for GLSL shaders
 Bugfixes:
  - Util: Fix PowerPC PNG read/write pixel order
  - Qt: Use safer isLoaded check in GameController

src/platform/opengl/gles2.c

@@ -84,18 +84,35 @@ static void GBAGLES2ContextInit(struct VideoBackend* v, WHandle handle) {
 
 	struct GBAGLES2Uniform* uniforms = malloc(sizeof(struct GBAGLES2Uniform) * 3);
 	uniforms[0].name = "gamma";
+	uniforms[0].readableName = "Gamma";
 	uniforms[0].type = GL_FLOAT;
 	uniforms[0].value.f = 1.0f;
+	uniforms[0].min.f = 0.1f;
+	uniforms[0].max.f = 3.0f;
 	uniforms[1].name = "scale";
+	uniforms[1].readableName = "Scale";
 	uniforms[1].type = GL_FLOAT_VEC3;
 	uniforms[1].value.fvec3[0] = 1.0f;
 	uniforms[1].value.fvec3[1] = 1.0f;
 	uniforms[1].value.fvec3[2] = 1.0f;
+	uniforms[1].min.fvec3[0] = -1.0f;
+	uniforms[1].min.fvec3[1] = -1.0f;
+	uniforms[1].min.fvec3[2] = -1.0f;
+	uniforms[1].max.fvec3[0] = 2.0f;
+	uniforms[1].max.fvec3[1] = 2.0f;
+	uniforms[1].max.fvec3[2] = 2.0f;
 	uniforms[2].name = "bias";
+	uniforms[2].readableName = "Bias";
 	uniforms[2].type = GL_FLOAT_VEC3;
 	uniforms[2].value.fvec3[0] = 0.0f;
 	uniforms[2].value.fvec3[1] = 0.0f;
 	uniforms[2].value.fvec3[2] = 0.0f;
+	uniforms[2].min.fvec3[0] = -1.0f;
+	uniforms[2].min.fvec3[1] = -1.0f;
+	uniforms[2].min.fvec3[2] = -1.0f;
+	uniforms[2].max.fvec3[0] = 1.0f;
+	uniforms[2].max.fvec3[1] = 1.0f;
+	uniforms[2].max.fvec3[2] = 1.0f;
 	GBAGLES2ShaderInit(&context->initialShader, _vertexShader, _fragmentShader, -1, -1, uniforms, 3);
 	GBAGLES2ShaderInit(&context->finalShader, 0, 0, 0, 0, 0, 0);
 	glDeleteFramebuffers(1, &context->finalShader.fbo);

src/platform/qt/DisplayGL.cpp

@@ -208,6 +208,19 @@ PainterGL::PainterGL(QGLWidget* parent, QGLFormat::OpenGLVersionFlags glVersion)
 		PainterGL* painter = static_cast<PainterGL*>(v->user);
 		painter->m_gl->swapBuffers();
 	};
+
+	m_gl->makeCurrent();
+#if defined(_WIN32) && defined(USE_EPOXY)
+	epoxy_handle_external_wglMakeCurrent();
+#endif
+	m_backend->init(m_backend, reinterpret_cast<WHandle>(m_gl->winId()));
+#if !defined(_WIN32) || defined(USE_EPOXY)
+	if (m_supportsShaders) {
+		m_shader.preprocessShader = static_cast<void*>(&reinterpret_cast<GBAGLES2Context*>(m_backend)->initialShader);
+	}
+#endif
+	m_gl->doneCurrent();
+
 	m_backend->user = this;
 	m_backend->filter = false;
 	m_backend->lockAspectRatio = false;
@@ -224,11 +237,14 @@ PainterGL::~PainterGL() {
 	for (auto item : m_free) {
 		delete[] item;
 	}
-	delete m_backend;
-	m_backend = nullptr;
+#if !defined(_WIN32) || defined(USE_EPOXY)
 	if (m_shader.passes) {
 		GBAGLES2ShaderFree(&m_shader);
 	}
+#endif
+	m_backend->deinit(m_backend);
+	delete m_backend;
+	m_backend = nullptr;
 }
 
 void PainterGL::setContext(GBAThread* context) {
@@ -265,10 +281,9 @@ void PainterGL::start() {
 #if defined(_WIN32) && defined(USE_EPOXY)
 	epoxy_handle_external_wglMakeCurrent();
 #endif
-	m_backend->init(m_backend, reinterpret_cast<WHandle>(m_gl->winId()));
 
 #if !defined(_WIN32) || defined(USE_EPOXY)
-	if (m_shader.passes) {
+	if (m_supportsShaders && m_shader.passes) {
 		GBAGLES2ShaderAttach(reinterpret_cast<GBAGLES2Context*>(m_backend), static_cast<GBAGLES2Shader*>(m_shader.passes), m_shader.nPasses);
 	}
 #endif
@@ -314,7 +329,6 @@ void PainterGL::stop() {
 	dequeueAll();
 	m_backend->clear(m_backend);
 	m_backend->swap(m_backend);
-	m_backend->deinit(m_backend);
 	m_gl->doneCurrent();
 	m_gl->context()->moveToThread(m_gl->thread());
 	moveToThread(m_gl->thread());

src/platform/qt/ShaderSelector.cpp

@@ -106,14 +106,60 @@ void ShaderSelector::refreshShaders() {
 	}
 
 #if !defined(_WIN32) || defined(USE_EPOXY)
+	m_ui.passes->addTab(makePage(static_cast<GBAGLES2Shader*>(m_shaders->preprocessShader)), tr("Preprocessing"));
 	GBAGLES2Shader* shaders = static_cast<GBAGLES2Shader*>(m_shaders->passes);
 	for (size_t p = 0; p < m_shaders->nPasses; ++p) {
+		QWidget* page = makePage(&shaders[p]);
+		if (page) {
+			m_ui.passes->addTab(page, tr("Pass %1").arg(p + 1));
+		}
+	}
+#endif
+}
+
+void ShaderSelector::addUniform(QGridLayout* settings, float* value, float min, float max, int y, int x) {
+	QDoubleSpinBox* f = new QDoubleSpinBox;
+	f->setDecimals(3);
+	if (min < max) {
+		f->setMinimum(min);
+		f->setMaximum(max);
+	}
+	f->setValue(*value);
+	f->setSingleStep(0.001);
+	f->setAccelerated(true);
+	settings->addWidget(f, y, x);
+	connect(f, static_cast<void (QDoubleSpinBox::*)(double)>(&QDoubleSpinBox::valueChanged), [value](double v) {
+		*value = v;
+		// TODO: Config
+	});
+}
+
+void ShaderSelector::addUniform(QGridLayout* settings, int* value, int min, int max, int y, int x) {
+	QSpinBox* i = new QSpinBox;
+	if (min < max) {
+		i->setMinimum(min);
+		i->setMaximum(max);
+	}
+	i->setValue(*value);
+	i->setSingleStep(1);
+	i->setAccelerated(true);
+	settings->addWidget(i, y, x);
+	connect(i, static_cast<void (QSpinBox::*)(int)>(&QSpinBox::valueChanged), [value](int v) {
+		*value = v;
+		// TODO: Config
+	});
+}
+
+QWidget* ShaderSelector::makePage(GBAGLES2Shader* shader) {
+	if (!shader->nUniforms) {
+		return nullptr;
+	}
 	QWidget* page = new QWidget;
 	QFormLayout* layout = new QFormLayout;
 	page->setLayout(layout);
-		for (size_t u = 0 ; u < shaders[p].nUniforms; ++u) {
+	for (size_t u = 0 ; u < shader->nUniforms; ++u) {
 		QGridLayout* settings = new QGridLayout;
-			GBAGLES2Uniform* uniform = &shaders[p].uniforms[u];
+		GBAGLES2Uniform* uniform = &shader->uniforms[u];
 		switch (uniform->type) {
 		case GL_FLOAT:
 			addUniform(settings, &uniform->value.f, uniform->min.f, uniform->max.f, 0, 0);
@@ -152,42 +198,7 @@ void ShaderSelector::refreshShaders() {
 			addUniform(settings, &uniform->value.ivec4[3], uniform->min.ivec4[3], uniform->max.ivec4[3], 0, 3);
 			break;
 		}
-			layout->addRow(shaders[p].uniforms[u].readableName, settings);
+		layout->addRow(shader->uniforms[u].readableName, settings);
 	}
-		m_ui.passes->addTab(page, tr("Pass %1").arg(p + 1));
-	}
-#endif
-}
-
-void ShaderSelector::addUniform(QGridLayout* settings, float* value, float min, float max, int y, int x) {
-	QDoubleSpinBox* f = new QDoubleSpinBox;
-	f->setDecimals(3);
-	if (min < max) {
-		f->setMinimum(min);
-		f->setMaximum(max);
-	}
-	f->setValue(*value);
-	f->setSingleStep(0.001);
-	f->setAccelerated(true);
-	settings->addWidget(f, y, x);
-	connect(f, static_cast<void (QDoubleSpinBox::*)(double)>(&QDoubleSpinBox::valueChanged), [value](double v) {
-		*value = v;
-		// TODO: Config
-	});
-}
-
-void ShaderSelector::addUniform(QGridLayout* settings, int* value, int min, int max, int y, int x) {
-	QSpinBox* i = new QSpinBox;
-	if (min < max) {
-		i->setMinimum(min);
-		i->setMaximum(max);
-	}
-	i->setValue(*value);
-	i->setSingleStep(1);
-	i->setAccelerated(true);
-	settings->addWidget(i, y, x);
-	connect(i, static_cast<void (QSpinBox::*)(int)>(&QSpinBox::valueChanged), [value](int v) {
-		*value = v;
-		// TODO: Config
-	});
+	return page;
 }

src/platform/qt/ShaderSelector.h

@@ -10,6 +10,7 @@
 
 #include "ui_ShaderSelector.h"
 
+struct GBAGLES2Shader;
 class QGridLayout;
 struct VideoShader;
 
@@ -36,6 +37,7 @@ private slots:
 private:
 	void addUniform(QGridLayout*, float* value, float min, float max, int y, int x);
 	void addUniform(QGridLayout*, int* value, int min, int max, int y, int x);
+	QWidget* makePage(GBAGLES2Shader*);
 
 	Ui::ShaderSelector m_ui;
 	Display* m_display;

src/platform/video-backend.h

@@ -36,6 +36,7 @@ struct VideoShader {
 	const char* name;
 	const char* author;
 	const char* description;
+	void* preprocessShader;
 	void* passes;
 	size_t nPasses;
 };