new bloom render tasks, setup util and hdr bloom code example

framework/opengl_renderer/src/mm/opengl/bloom.cpp

@@ -0,0 +1,158 @@
+#include "./bloom.hpp"
+
+#include <mm/opengl/render_tasks/bloom_extraction.hpp>
+#include <mm/opengl/render_tasks/blur.hpp>
+#include <mm/opengl/render_tasks/bloom_combine.hpp>
+
+#include <mm/opengl/fbo_builder.hpp>
+#include <mm/opengl/texture_loader.hpp>
+
+namespace MM::OpenGL {
+
+using namespace entt::literals;
+
+void setup_bloom(
+	MM::Engine& engine,
+	const std::string color_src_tex,
+	const size_t bloom_phases,
+	const float bloom_in_scale,
+	const float bloom_phase_scale
+) {
+	assert(bloom_phases > 1);
+	auto& rs = engine.getService<MM::Services::OpenGLRenderer>();
+	auto& rm_t = MM::ResourceManager<MM::OpenGL::Texture>::ref();
+	auto [w, h] = engine.getService<MM::Services::SDLService>().getWindowSize();
+
+#ifdef MM_OPENGL_3_GLES
+	#if 0 // NOPE!!
+	// TODO: caps at 1, invest in half float?
+	const auto bloom_internal_format = GL_RGB565; // prolly fine
+	const auto bloom_format_type = GL_UNSIGNED_BYTE;
+	#else
+	const auto bloom_internal_format = GL_RGB16F;
+	const auto bloom_format_type = GL_FLOAT;
+	#endif
+#else
+	const auto bloom_internal_format = GL_RGB16F;
+	const auto bloom_format_type = GL_FLOAT;
+#endif
+
+	{ // bloom in (bloom extraction)
+		rm_t.reload<MM::OpenGL::TextureLoaderEmpty>(
+			"bloom_in",
+			bloom_internal_format,
+			w * bloom_in_scale, h * bloom_in_scale,
+			GL_RGB, bloom_format_type
+		);
+		{ // filter
+			rm_t.get("bloom_in"_hs)->bind(0);
+			glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
+			glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
+
+			glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
+			glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
+		}
+
+		rs.targets["bloom_extraction"] = MM::OpenGL::FBOBuilder::start()
+			.attachTexture(rm_t.get("bloom_in"_hs), GL_COLOR_ATTACHMENT0)
+			.setResizeFactors(bloom_in_scale, bloom_in_scale)
+			.setResize(true)
+			.finish();
+		assert(rs.targets["bloom_extraction"]);
+	}
+
+	// blur textures and fbos
+	for (size_t i = 1; i <= bloom_phases; i++) {
+		// TODO: further dedup
+		std::string tex_out_name {"blur_out" + std::to_string(i)};
+		auto tex_out_id = entt::hashed_string::value(tex_out_name.c_str());
+		rm_t.reload<MM::OpenGL::TextureLoaderEmpty>(
+			tex_out_id,
+			bloom_internal_format,
+			w * bloom_in_scale * glm::pow(bloom_phase_scale, i), h * bloom_in_scale * glm::pow(bloom_phase_scale, i),
+			GL_RGB, bloom_format_type
+		);
+		{ // filter
+			rm_t.get(tex_out_id)->bind(0);
+			glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
+			glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
+
+			glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
+			glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
+		}
+
+		std::string tex_tmp_name {"blur_tmp" + std::to_string(i)};
+		auto tex_tmp_id = entt::hashed_string::value(tex_tmp_name.c_str());
+		rm_t.reload<MM::OpenGL::TextureLoaderEmpty>(
+			tex_tmp_id,
+			bloom_internal_format,
+			w * bloom_in_scale * glm::pow(bloom_phase_scale, i), h * bloom_in_scale * glm::pow(bloom_phase_scale, i),
+			GL_RGB, bloom_format_type
+		);
+		{ // filter
+			rm_t.get(tex_tmp_id)->bind(0);
+			glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
+			glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
+
+			glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
+			glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
+		}
+
+		rs.targets[tex_out_name] = MM::OpenGL::FBOBuilder::start()
+			.attachTexture(rm_t.get(tex_out_id), GL_COLOR_ATTACHMENT0)
+			.setResizeFactors(bloom_in_scale * glm::pow(bloom_phase_scale, i), bloom_in_scale * glm::pow(bloom_phase_scale, i))
+			.setResize(true)
+			.finish();
+		assert(rs.targets[tex_out_name]);
+
+		rs.targets[tex_tmp_name] = MM::OpenGL::FBOBuilder::start()
+			.attachTexture(rm_t.get(tex_tmp_id), GL_COLOR_ATTACHMENT0)
+			.setResizeFactors(bloom_in_scale * glm::pow(bloom_phase_scale, i), bloom_in_scale * glm::pow(bloom_phase_scale, i))
+			.setResize(true)
+			.finish();
+		assert(rs.targets[tex_tmp_name]);
+	}
+
+	{ // render tasks
+		auto& extraction = rs.addRenderTask<MM::OpenGL::RenderTasks::BloomExtraction>(engine);
+		extraction.src_tex = color_src_tex;
+		extraction.target_fbo = "bloom_extraction";
+
+		const glm::vec2 blur_factor {1.f, 1.f};
+
+		{ // blur rt
+			std::string prev_out_tex = "bloom_in";
+			for (size_t i = 1; i <= bloom_phases; i++) {
+				auto& blur = rs.addRenderTask<MM::OpenGL::RenderTasks::Blur>(engine);
+				// h
+				blur.in_tex = prev_out_tex;
+				blur.temp_fbo = "blur_tmp" + std::to_string(i);
+				// v
+				blur.temp_tex = "blur_tmp" + std::to_string(i);
+				blur.out_fbo = "blur_out" + std::to_string(i);
+				blur.out_tex = "blur_out" + std::to_string(i);
+				blur.tex_offset_factor = blur_factor * glm::vec2{2.f, 1.f}; // the input texture is double the size
+
+				// old blur:
+				//blur.tex_offset = {1.f/(w * bloom_in_scale * bloom_in_scale), 1.f/(h * bloom_in_scale * bloom_in_scale)};
+
+				prev_out_tex = blur.out_tex;
+			}
+		}
+
+		// combine passes
+		for (size_t i = bloom_phases; i > 1; i--) {
+			auto& combine = rs.addRenderTask<MM::OpenGL::RenderTasks::BloomCombine>(engine);
+			if (i == bloom_phases) {
+				combine.tex0 = "blur_out" + std::to_string(i);
+			} else {
+				combine.tex0 = "blur_tmp" + std::to_string(i);
+			}
+			combine.tex1 = "blur_out" + std::to_string(i-1);
+			combine.target_fbo = "blur_tmp" + std::to_string(i-1); // -> blur_tmpi-1
+		}
+	}
+}
+
+} // MM::OpenGL
+