Rework testing code

source/glad.c

@@ -1,22 +1,23 @@
 /*
 
-    OpenGL loader generated by glad 0.1.36 on Sun May 26 16:07:25 2024.
+    OpenGL loader generated by glad 0.1.36 on Mon May 27 15:25:59 2024.
 
     Language/Generator: C/C++
     Specification: gl
     APIs: gl=4.5
     Profile: core
     Extensions:
-        GL_AMD_vertex_shader_layer
+        GL_AMD_vertex_shader_layer,
+        GL_ARB_shader_viewport_layer_array
     Loader: True
     Local files: False
     Omit khrplatform: False
     Reproducible: False
 
     Commandline:
-        --profile="core" --api="gl=4.5" --generator="c" --spec="gl" --extensions="GL_AMD_vertex_shader_layer"
+        --profile="core" --api="gl=4.5" --generator="c" --spec="gl" --extensions="GL_AMD_vertex_shader_layer,GL_ARB_shader_viewport_layer_array"
     Online:
-        https://glad.dav1d.de/#profile=core&language=c&specification=gl&loader=on&api=gl%3D4.5&extensions=GL_AMD_vertex_shader_layer
+        https://glad.dav1d.de/#profile=core&language=c&specification=gl&loader=on&api=gl%3D4.5&extensions=GL_AMD_vertex_shader_layer&extensions=GL_ARB_shader_viewport_layer_array
 */
 
 #include <stdio.h>
@@ -969,6 +970,7 @@ PFNGLVIEWPORTINDEXEDFPROC glad_glViewportIndexedf = NULL;
 PFNGLVIEWPORTINDEXEDFVPROC glad_glViewportIndexedfv = NULL;
 PFNGLWAITSYNCPROC glad_glWaitSync = NULL;
 int GLAD_GL_AMD_vertex_shader_layer = 0;
+int GLAD_GL_ARB_shader_viewport_layer_array = 0;
 static void load_GL_VERSION_1_0(GLADloadproc load) {
 	if(!GLAD_GL_VERSION_1_0) return;
 	glad_glCullFace = (PFNGLCULLFACEPROC)load("glCullFace");
@@ -1725,6 +1727,7 @@ static void load_GL_VERSION_4_5(GLADloadproc load) {
 static int find_extensionsGL(void) {
 	if (!get_exts()) return 0;
 	GLAD_GL_AMD_vertex_shader_layer = has_ext("GL_AMD_vertex_shader_layer");
+	GLAD_GL_ARB_shader_viewport_layer_array = has_ext("GL_ARB_shader_viewport_layer_array");
 	free_exts();
 	return 1;
 }

source/glad/glad.h

@@ -1,22 +1,23 @@
 /*
 
-    OpenGL loader generated by glad 0.1.36 on Sun May 26 16:07:25 2024.
+    OpenGL loader generated by glad 0.1.36 on Mon May 27 15:25:59 2024.
 
     Language/Generator: C/C++
     Specification: gl
     APIs: gl=4.5
     Profile: core
     Extensions:
-        GL_AMD_vertex_shader_layer
+        GL_AMD_vertex_shader_layer,
+        GL_ARB_shader_viewport_layer_array
     Loader: True
     Local files: False
     Omit khrplatform: False
     Reproducible: False
 
     Commandline:
-        --profile="core" --api="gl=4.5" --generator="c" --spec="gl" --extensions="GL_AMD_vertex_shader_layer"
+        --profile="core" --api="gl=4.5" --generator="c" --spec="gl" --extensions="GL_AMD_vertex_shader_layer,GL_ARB_shader_viewport_layer_array"
     Online:
-        https://glad.dav1d.de/#profile=core&language=c&specification=gl&loader=on&api=gl%3D4.5&extensions=GL_AMD_vertex_shader_layer
+        https://glad.dav1d.de/#profile=core&language=c&specification=gl&loader=on&api=gl%3D4.5&extensions=GL_AMD_vertex_shader_layer&extensions=GL_ARB_shader_viewport_layer_array
 */
 
 
@@ -3652,6 +3653,10 @@ GLAPI PFNGLTEXTUREBARRIERPROC glad_glTextureBarrier;
 #define GL_AMD_vertex_shader_layer 1
 GLAPI int GLAD_GL_AMD_vertex_shader_layer;
 #endif
+#ifndef GL_ARB_shader_viewport_layer_array
+#define GL_ARB_shader_viewport_layer_array 1
+GLAPI int GLAD_GL_ARB_shader_viewport_layer_array;
+#endif
 
 #ifdef __cplusplus
 }

source/glerminal-private.h

@@ -63,6 +63,8 @@ namespace glerminal
 		unsigned int m_sprites_texture;
 		unsigned int m_framebuffer;
 		unsigned int m_framebuffer_backing_texture;
+		unsigned int m_screen_framebuffer;
+		unsigned int m_screen_framebuffer_backing_texture;
 		unsigned int m_layer_colors_buffer;
 		unsigned int m_layer_scales_buffer;
 		unsigned int m_screen_size_uniform_location;
@@ -85,8 +87,8 @@ namespace glerminal
 
 #ifdef GLERMINAL_OPENGL_DEBUG_CONTEXT
 		mutable std::ofstream m_log;
-		void log(GLenum type, GLuint id, GLenum severity, const char* message) const;
 #endif
+		void log(GLenum type, GLuint id, GLenum severity, const char* message) const;
 
 		void init_glfw();
 		void init_gl();

source/glerminal.cpp

@@ -53,8 +53,9 @@ namespace
 		"}";
 
 	// note: AMD_vertex_shader_layer support required
-	constexpr char VERTEX_SHADER_AMD_SOURCE[] =
+	constexpr char VERTEX_SHADER_ARB_SOURCE[] =
 		"#version 450 core\n"
+		"#extension GL_ARB_shader_viewport_layer_array : enable\n"
 		"#extension GL_AMD_vertex_shader_layer : enable\n"
 		"layout (location = 0) in vec2 position;\n"
 		"layout (location = 1) in vec2 offset;\n"
@@ -81,7 +82,7 @@ namespace
 		"}";
 
 	constexpr const char* VERTEX_SHADER_SOURCE_PTR = VERTEX_SHADER_SOURCE;
-	constexpr const char* VERTEX_SHADER_AMD_SOURCE_PTR = VERTEX_SHADER_AMD_SOURCE;
+	constexpr const char* VERTEX_SHADER_ARB_SOURCE_PTR = VERTEX_SHADER_ARB_SOURCE;
 
 	constexpr char GEOMETRY_SHADER_SOURCE[] =
 		"#version 450 core\n"
@@ -128,7 +129,7 @@ namespace
 		"}";
 
 	// note: AMD_vertex_shader_layer support required
-	constexpr char FRAGMENT_SHADER_AMD_SOURCE[] =
+	constexpr char FRAGMENT_SHADER_ARB_SOURCE[] =
 		"#version 450 core\n"
 		"in VS_OUT {\n"
 		"	flat int sprite;\n"
@@ -142,7 +143,7 @@ namespace
 		"}";
 
 	constexpr const char* FRAGMENT_SHADER_SOURCE_PTR = FRAGMENT_SHADER_SOURCE;
-	constexpr const char* FRAGMENT_SHADER_AMD_SOURCE_PTR = FRAGMENT_SHADER_AMD_SOURCE;
+	constexpr const char* FRAGMENT_SHADER_ARB_SOURCE_PTR = FRAGMENT_SHADER_ARB_SOURCE;
 
 	constexpr char SCREEN_VERTEX_SHADER_SOURCE[] =
 		"#version 450 core\n"
@@ -156,7 +157,7 @@ namespace
 
 	constexpr const char* SCREEN_VERTEX_SHADER_SOURCE_PTR = SCREEN_VERTEX_SHADER_SOURCE;
 
-	constexpr char* SCREEN_FRAGMENT_SHADER_SOURCE =
+	constexpr char SCREEN_FRAGMENT_SHADER_SOURCE[] =
 		"#version 450 core\n"
 		"in vec2 texcoord;\n"
 		"layout (binding = 1) uniform sampler2DArray " LAYERS_UNIFORM_NAME ";\n"
@@ -266,11 +267,13 @@ namespace glerminal
 		glDrawArraysInstanced(GL_TRIANGLES, 0, 6, GRID_AREA * LAYER_COUNT);
 
 		glUseProgram(m_screen_program);
-		glBindFramebuffer(GL_FRAMEBUFFER, 0);
+		glBindFramebuffer(GL_FRAMEBUFFER, m_screen_framebuffer);
 		glBindVertexArray(m_screen_vao);
 		glClear(GL_COLOR_BUFFER_BIT);
 		glDrawArrays(GL_TRIANGLES, 0, 6);
 
+		glBlitNamedFramebuffer(m_screen_framebuffer, 0, 0, 0, SCREEN_WIDTH, SCREEN_HEIGHT, 0, 0, SCREEN_WIDTH, SCREEN_HEIGHT, GL_COLOR_BUFFER_BIT, GL_NEAREST);
+
 		glfwSwapBuffers(m_window);
 	}
 
@@ -363,12 +366,12 @@ namespace glerminal
 		}
 	}
 	
-#ifdef GLERMINAL_OPENGL_DEBUG_CONTEXT
 	void glerminal::log(GLenum type, GLuint id, GLenum severity, const char* message) const
 	{
+#ifdef GLERMINAL_OPENGL_DEBUG_CONTEXT
 		glDebugMessageInsert(GL_DEBUG_SOURCE_THIRD_PARTY, type, id, severity, -1, message);
-	}
 #endif
+	}
 
 	void glerminal::init_gl()
 	{
@@ -494,11 +497,12 @@ namespace glerminal
 
 		// -- setup shader program --
 		// test for features
-		const bool vertex_shader_layer_supported = glfwExtensionSupported("GL_AMD_vertex_shader_layer");
+		const bool vertex_shader_layer_supported =
+			glfwExtensionSupported("GL_ARB_shader_viewport_layer_array") || glfwExtensionSupported("GL_AMD_vertex_shader_layer");
 
 		// compile
 		const unsigned int vertex_shader = glCreateShader(GL_VERTEX_SHADER);
-		glShaderSource(vertex_shader, 1, &(vertex_shader_layer_supported ? VERTEX_SHADER_AMD_SOURCE_PTR : VERTEX_SHADER_SOURCE_PTR), nullptr);
+		glShaderSource(vertex_shader, 1, &(vertex_shader_layer_supported ? VERTEX_SHADER_ARB_SOURCE_PTR : VERTEX_SHADER_SOURCE_PTR), nullptr);
 		glCompileShader(vertex_shader);
 
 		const unsigned int geometry_shader = glCreateShader(GL_GEOMETRY_SHADER);
@@ -506,12 +510,12 @@ namespace glerminal
 		glCompileShader(geometry_shader);
 
 		const unsigned int fragment_shader = glCreateShader(GL_FRAGMENT_SHADER);
-		glShaderSource(fragment_shader, 1, &(vertex_shader_layer_supported ? FRAGMENT_SHADER_AMD_SOURCE_PTR : FRAGMENT_SHADER_SOURCE_PTR), nullptr);
+		glShaderSource(fragment_shader, 1, &(vertex_shader_layer_supported ? FRAGMENT_SHADER_ARB_SOURCE_PTR : FRAGMENT_SHADER_SOURCE_PTR), nullptr);
 		glCompileShader(fragment_shader);
 
 		constexpr int INFO_LOG_SIZE = 512;
 		int success;
-		char info_log[INFO_LOG_SIZE];
+		char info_log[INFO_LOG_SIZE + 1] = {};
 
 		// verify compile
 		glGetShaderiv(vertex_shader, GL_COMPILE_STATUS, &success);
@@ -523,7 +527,9 @@ namespace glerminal
 			glDeleteShader(geometry_shader);
 			glDeleteShader(fragment_shader);
 
-			throw std::runtime_error("Could not compile vertex shader.");
+			log(GL_DEBUG_TYPE_ERROR, 0, 0, "Could not compile vertex shader.");
+			log(GL_DEBUG_TYPE_ERROR, 0, 0, info_log);
+			throw std::runtime_error("");
 		}
 
 		glGetShaderiv(geometry_shader, GL_COMPILE_STATUS, &success);
@@ -535,7 +541,9 @@ namespace glerminal
 			glDeleteShader(geometry_shader);
 			glDeleteShader(fragment_shader);
 
-			throw std::runtime_error("Could not compile geometry shader.");
+			log(GL_DEBUG_TYPE_ERROR, 1, 0, "Could not compile geometry shader.");
+			log(GL_DEBUG_TYPE_ERROR, 1, 0, info_log);
+			throw std::runtime_error("");
 		}
 
 		glGetShaderiv(fragment_shader, GL_COMPILE_STATUS, &success);
@@ -547,7 +555,9 @@ namespace glerminal
 			glDeleteShader(geometry_shader);
 			glDeleteShader(fragment_shader);
 
-			throw std::runtime_error("Could not compile fragment shader.");
+			log(GL_DEBUG_TYPE_ERROR, 2, 0, "Could not compile fragment shader.");
+			log(GL_DEBUG_TYPE_ERROR, 2, 0, info_log);
+			throw std::runtime_error("");
 		}
 
 		// link
@@ -572,7 +582,9 @@ namespace glerminal
 
 			glDeleteProgram(m_program);
 
-			throw std::runtime_error("Could not link shader program.");
+			log(GL_DEBUG_TYPE_ERROR, 3, 0, "Could not link shader program.");
+			log(GL_DEBUG_TYPE_ERROR, 3, 0, info_log);
+			throw std::runtime_error("");
 		}
 
 		// setup uniforms
@@ -599,7 +611,9 @@ namespace glerminal
 			glDeleteShader(screen_vertex_shader);
 			glDeleteShader(screen_fragment_shader);
 
-			throw std::runtime_error("Could not compile screen vertex shader.");
+			log(GL_DEBUG_TYPE_ERROR, 4, 0, "Could not compile screen vertex shader.");
+			log(GL_DEBUG_TYPE_ERROR, 4, 0, info_log);
+			throw std::runtime_error("");
 		}
 
 		glGetShaderiv(screen_fragment_shader, GL_COMPILE_STATUS, &success);
@@ -610,7 +624,9 @@ namespace glerminal
 			glDeleteShader(screen_vertex_shader);
 			glDeleteShader(screen_fragment_shader);
 
-			throw std::runtime_error("Could not compile screen fragment shader.");
+			log(GL_DEBUG_TYPE_ERROR, 5, 0, "Could not compile screen fragment shader.");
+			log(GL_DEBUG_TYPE_ERROR, 5, 0, info_log);
+			throw std::runtime_error("");
 		}
 
 		// link
@@ -627,10 +643,15 @@ namespace glerminal
 		{
 			glDeleteProgram(m_screen_program);
 
-			throw std::runtime_error("Could not link screen shader program.");
+			log(GL_DEBUG_TYPE_ERROR, 6, 0, "Could not link screen shader program.");
+			log(GL_DEBUG_TYPE_ERROR, 6, 0, info_log);
+			throw std::runtime_error("");
 		}
 
-		// setup uniforms later
+		// setup uniforms for screen shader
+		glUseProgram(m_screen_program);
+
+		glUniform1i(glGetUniformLocation(m_screen_program, LAYER_COUNT_UNIFORM_NAME), LAYER_COUNT);
 
 		// -- setup textures --
 		glGenTextures(1, &m_sprites_texture);
@@ -670,10 +691,24 @@ namespace glerminal
 
 		glBindTextureUnit(1, m_framebuffer_backing_texture);
 
-		// setup uniforms for screen shader
+		// -- setup screen framebuffer --
-		glUseProgram(m_screen_program);
+		glGenFramebuffers(1, &m_screen_framebuffer);
+		glBindFramebuffer(GL_FRAMEBUFFER, m_screen_framebuffer);
 
-		glUniform1i(glGetUniformLocation(m_screen_program, LAYER_COUNT_UNIFORM_NAME), LAYER_COUNT);
+		glGenTextures(1, &m_screen_framebuffer_backing_texture);
+		glBindTexture(GL_TEXTURE_2D, m_screen_framebuffer_backing_texture);
+
+		glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
+		glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
+
+		glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
+		glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
+
+		glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_BASE_LEVEL, 0);
+		glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAX_LEVEL, 0);
+
+		glTexStorage2D(GL_TEXTURE_2D, 1, GL_RGB8, SCREEN_WIDTH, SCREEN_HEIGHT);
+		glFramebufferTexture(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, m_screen_framebuffer_backing_texture, 0);
 	}
 
 	void glerminal::deinit_glfw()
@@ -685,6 +720,8 @@ namespace glerminal
 
 	void glerminal::deinit_gl()
 	{
+		glDeleteFramebuffers(1, &m_screen_framebuffer);
+		glDeleteTextures(1, &m_screen_framebuffer_backing_texture);
 		glDeleteFramebuffers(1, &m_framebuffer);
 		glDeleteTextures(1, &m_framebuffer_backing_texture);
 		glDeleteTextures(1, &m_sprites_texture);

tests/test-common/test-common.cpp

@@ -13,8 +13,12 @@ namespace
 
 void glerminal_test_save_image()
 {
-	glReadBuffer(GL_LEFT);
+	// -- DIRTY HACK --
-	glReadPixels(0, 0, GRID_WIDTH * CELL_SCALE * 8, GRID_HEIGHT * CELL_SCALE * 8, GL_RGB, GL_UNSIGNED_BYTE, pixels);
+	// 
+	// GL_TEXTURE_2D is not rebound after setting up screen framebuffer
+	// This code will break if this behavior changes
+
+	glGetTexImage(GL_TEXTURE_2D, 0, GL_RGB, GL_UNSIGNED_BYTE, pixels);
 
 	stbi_flip_vertically_on_write(true);
 	stbi_write_png("image.png", GRID_WIDTH * CELL_SCALE * 8, GRID_HEIGHT * CELL_SCALE * 8, 3, pixels, 1280 * 3);