Implement glow/bloom on compatibility renderer

1 files changed, 172 insertions, 0 deletions

diff --git a/drivers/gles3/effects/glow.cpp b/drivers/gles3/effects/glow.cpp
new file mode 100644
index 0000000000..9fc2eef65b
--- /dev/null
+++ b/drivers/gles3/effects/glow.cpp
@@ -0,0 +1,172 @@
+/**************************************************************************/
+/*  glow.cpp                                                              */
+/**************************************************************************/
+/*                         This file is part of:                          */
+/*                             GODOT ENGINE                               */
+/*                        https://godotengine.org                         */
+/**************************************************************************/
+/* Copyright (c) 2014-present Godot Engine contributors (see AUTHORS.md). */
+/* Copyright (c) 2007-2014 Juan Linietsky, Ariel Manzur.                  */
+/*                                                                        */
+/* Permission is hereby granted, free of charge, to any person obtaining  */
+/* a copy of this software and associated documentation files (the        */
+/* "Software"), to deal in the Software without restriction, including    */
+/* without limitation the rights to use, copy, modify, merge, publish,    */
+/* distribute, sublicense, and/or sell copies of the Software, and to     */
+/* permit persons to whom the Software is furnished to do so, subject to  */
+/* the following conditions:                                              */
+/*                                                                        */
+/* The above copyright notice and this permission notice shall be         */
+/* included in all copies or substantial portions of the Software.        */
+/*                                                                        */
+/* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,        */
+/* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF     */
+/* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. */
+/* IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY   */
+/* CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,   */
+/* TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE      */
+/* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.                 */
+/**************************************************************************/
+
+#ifdef GLES3_ENABLED
+
+#include "glow.h"
+
+using namespace GLES3;
+
+Glow *Glow::singleton = nullptr;
+
+Glow *Glow::get_singleton() {
+	return singleton;
+}
+
+Glow::Glow() {
+	singleton = this;
+
+	glow.shader.initialize();
+	glow.shader_version = glow.shader.version_create();
+
+	{ // Screen Triangle.
+		glGenBuffers(1, &screen_triangle);
+		glBindBuffer(GL_ARRAY_BUFFER, screen_triangle);
+
+		const float qv[6] = {
+			-1.0f,
+			-1.0f,
+			3.0f,
+			-1.0f,
+			-1.0f,
+			3.0f,
+		};
+
+		glBufferData(GL_ARRAY_BUFFER, sizeof(float) * 6, qv, GL_STATIC_DRAW);
+		glBindBuffer(GL_ARRAY_BUFFER, 0); //unbind
+
+		glGenVertexArrays(1, &screen_triangle_array);
+		glBindVertexArray(screen_triangle_array);
+		glBindBuffer(GL_ARRAY_BUFFER, screen_triangle);
+		glVertexAttribPointer(RS::ARRAY_VERTEX, 2, GL_FLOAT, GL_FALSE, sizeof(float) * 2, nullptr);
+		glEnableVertexAttribArray(RS::ARRAY_VERTEX);
+		glBindVertexArray(0);
+		glBindBuffer(GL_ARRAY_BUFFER, 0); //unbind
+	}
+}
+
+Glow::~Glow() {
+	glDeleteBuffers(1, &screen_triangle);
+	glDeleteVertexArrays(1, &screen_triangle_array);
+
+	glow.shader.version_free(glow.shader_version);
+
+	singleton = nullptr;
+}
+
+void Glow::_draw_screen_triangle() {
+	glBindVertexArray(screen_triangle_array);
+	glDrawArrays(GL_TRIANGLES, 0, 3);
+	glBindVertexArray(0);
+}
+
+void Glow::process_glow(GLuint p_source_color, Size2i p_size, const Glow::GLOWLEVEL *p_glow_buffers, uint32_t p_view, bool p_use_multiview) {
+	ERR_FAIL_COND(p_source_color == 0);
+	ERR_FAIL_COND(p_glow_buffers[3].color == 0);
+
+	// Reset some OpenGL state...
+	glDisable(GL_BLEND);
+	glDisable(GL_DEPTH_TEST);
+	glDepthMask(GL_FALSE);
+
+	// Start with our filter pass
+	{
+		glBindFramebuffer(GL_FRAMEBUFFER, p_glow_buffers[0].fbo);
+		glViewport(0, 0, p_glow_buffers[0].size.x, p_glow_buffers[0].size.y);
+
+		glActiveTexture(GL_TEXTURE0);
+		glBindTexture(p_use_multiview ? GL_TEXTURE_2D_ARRAY : GL_TEXTURE_2D, p_source_color);
+
+		uint64_t specialization = p_use_multiview ? GlowShaderGLES3::USE_MULTIVIEW : 0;
+		bool success = glow.shader.version_bind_shader(glow.shader_version, GlowShaderGLES3::MODE_FILTER, specialization);
+		if (!success) {
+			return;
+		}
+
+		glow.shader.version_set_uniform(GlowShaderGLES3::PIXEL_SIZE, 1.0 / p_glow_buffers[0].size.x, 1.0 / p_glow_buffers[0].size.y, glow.shader_version, GlowShaderGLES3::MODE_FILTER, specialization);
+		glow.shader.version_set_uniform(GlowShaderGLES3::VIEW, float(p_view), glow.shader_version, GlowShaderGLES3::MODE_FILTER, specialization);
+		glow.shader.version_set_uniform(GlowShaderGLES3::LUMINANCE_MULTIPLIER, luminance_multiplier, glow.shader_version, GlowShaderGLES3::MODE_FILTER, specialization);
+		glow.shader.version_set_uniform(GlowShaderGLES3::GLOW_BLOOM, glow_bloom, glow.shader_version, GlowShaderGLES3::MODE_FILTER, specialization);
+		glow.shader.version_set_uniform(GlowShaderGLES3::GLOW_HDR_THRESHOLD, glow_hdr_bleed_threshold, glow.shader_version, GlowShaderGLES3::MODE_FILTER, specialization);
+		glow.shader.version_set_uniform(GlowShaderGLES3::GLOW_HDR_SCALE, glow_hdr_bleed_scale, glow.shader_version, GlowShaderGLES3::MODE_FILTER, specialization);
+		glow.shader.version_set_uniform(GlowShaderGLES3::GLOW_LUMINANCE_CAP, glow_hdr_luminance_cap, glow.shader_version, GlowShaderGLES3::MODE_FILTER, specialization);
+
+		_draw_screen_triangle();
+	}
+
+	// Continue with downsampling
+	{
+		bool success = glow.shader.version_bind_shader(glow.shader_version, GlowShaderGLES3::MODE_DOWNSAMPLE, 0);
+		if (!success) {
+			return;
+		}
+
+		for (int i = 1; i < 4; i++) {
+			glBindFramebuffer(GL_FRAMEBUFFER, p_glow_buffers[i].fbo);
+			glViewport(0, 0, p_glow_buffers[i].size.x, p_glow_buffers[i].size.y);
+
+			glActiveTexture(GL_TEXTURE0);
+			glBindTexture(GL_TEXTURE_2D, p_glow_buffers[i - 1].color);
+
+			glow.shader.version_set_uniform(GlowShaderGLES3::PIXEL_SIZE, 1.0 / p_glow_buffers[i].size.x, 1.0 / p_glow_buffers[i].size.y, glow.shader_version, GlowShaderGLES3::MODE_DOWNSAMPLE);
+
+			_draw_screen_triangle();
+		}
+	}
+
+	// Now upsample
+	{
+		bool success = glow.shader.version_bind_shader(glow.shader_version, GlowShaderGLES3::MODE_UPSAMPLE, 0);
+		if (!success) {
+			return;
+		}
+
+		for (int i = 2; i >= 0; i--) {
+			glBindFramebuffer(GL_FRAMEBUFFER, p_glow_buffers[i].fbo);
+			glViewport(0, 0, p_glow_buffers[i].size.x, p_glow_buffers[i].size.y);
+
+			glActiveTexture(GL_TEXTURE0);
+			glBindTexture(GL_TEXTURE_2D, p_glow_buffers[i + 1].color);
+
+			glow.shader.version_set_uniform(GlowShaderGLES3::PIXEL_SIZE, 1.0 / p_glow_buffers[i].size.x, 1.0 / p_glow_buffers[i].size.y, glow.shader_version, GlowShaderGLES3::MODE_UPSAMPLE);
+
+			_draw_screen_triangle();
+		}
+	}
+
+	glDisable(GL_BLEND);
+	glEnable(GL_DEPTH_TEST);
+	glDepthMask(GL_TRUE);
+	glUseProgram(0);
+	glBindTexture(GL_TEXTURE_2D, 0);
+	glBindFramebuffer(GL_FRAMEBUFFER, 0);
+}
+
+#endif // GLES3_ENABLED