Further improvements to rendering subsystem

render/gles3/renderer.c

@@ -0,0 +1,161 @@
+#include <stdint.h>
+#include <stdlib.h>
+#include <assert.h>
+#include <GLES3/gl3.h>
+#include <wayland-util.h>
+#include <wayland-server-protocol.h>
+#include <wlr/render.h>
+#include <wlr/render/interface.h>
+#include <wlr/render/matrix.h>
+#include <common/log.h>
+#include "render/gles3.h"
+
+static struct {
+	bool initialized;
+	GLuint rgb, rgba;
+} shaders;
+static GLuint vao, vbo, ebo;
+
+static bool compile_shader(GLuint type, const GLchar *src, GLuint *shader) {
+	*shader = glCreateShader(type);
+	int len = strlen(src);
+	glShaderSource(*shader, 1, &src, &len);
+	glCompileShader(*shader);
+	GLint success;
+	glGetShaderiv(*shader, GL_COMPILE_STATUS, &success);
+	if (success == GL_FALSE) {
+		GLint loglen;
+		glGetShaderiv(*shader, GL_INFO_LOG_LENGTH, &loglen);
+		GLchar msg[loglen];
+		glGetShaderInfoLog(*shader, loglen, &loglen, msg);
+		return false;
+	}
+	return true;
+}
+
+static bool compile_program(const GLchar *vert_src,
+		const GLchar *frag_src, GLuint *program) {
+	GLuint vertex, fragment;
+	if (!compile_shader(GL_VERTEX_SHADER, vert_src, &vertex)) {
+		return false;
+	}
+	if (!compile_shader(GL_FRAGMENT_SHADER, frag_src, &fragment)) {
+		glDeleteProgram(vertex);
+		return false;
+	}
+	*program = glCreateProgram();
+	glAttachShader(*program, vertex);
+	glAttachShader(*program, fragment);
+	glLinkProgram(*program);
+	glDeleteProgram(vertex);
+	glDeleteProgram(fragment);
+	return true;
+}
+
+static void init_default_shaders() {
+	if (shaders.initialized) {
+		return;
+	}
+	if (!compile_program(vertex_src, fragment_src_RGB, &shaders.rgb)) {
+		goto error;
+	}
+	if (!compile_program(vertex_src, fragment_src_RGBA, &shaders.rgba)) {
+		goto error;
+	}
+	return;
+error:
+	wlr_log(L_ERROR, "Failed to set up default shaders!");
+}
+
+static void init_default_quad() {
+	GLfloat verticies[] = {
+		1, 1, 1, 1, // bottom right
+		1, 0, 1, 0, // top right
+		0, 0, 0, 0, // top left
+		0, 1, 0, 1, // bottom left
+	};
+	GLuint indicies[] = {
+		0, 1, 3,
+		1, 2, 3,
+	};
+
+	glGenVertexArrays(1, &vao);
+	glGenBuffers(1, &vbo);
+
+	glBindVertexArray(vao);
+	glBindBuffer(GL_ARRAY_BUFFER, vbo);
+
+	glEnableVertexAttribArray(0);
+	glEnableVertexAttribArray(1);
+	glVertexAttribPointer(0, 2, GL_FLOAT, GL_FALSE, 4 * sizeof(GLfloat), (void *)0);
+	glVertexAttribPointer(1, 2, GL_FLOAT, GL_FALSE, 4 * sizeof(GLfloat), (void *)(2 * sizeof(GLfloat)));
+	glBufferData(GL_ARRAY_BUFFER, sizeof(verticies), verticies, GL_STATIC_DRAW);
+
+	glGenBuffers(1, &ebo);
+	glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, ebo);
+	glBufferData(GL_ELEMENT_ARRAY_BUFFER, sizeof(indicies), indicies, GL_STATIC_DRAW);
+}
+
+static void init_globals() {
+	init_default_shaders();
+	init_default_quad();
+}
+
+static void wlr_gles3_begin(struct wlr_renderer_state *state,
+		struct wlr_output *output) {
+	// TODO: let users customize the clear color?
+	glClearColor(0.25f, 0.25f, 0.25f, 1);
+	glClear(GL_COLOR_BUFFER_BIT);
+	int32_t width = output->width;
+	int32_t height = output->height;
+	glViewport(0, 0, width, height);
+	// Note: maybe we should save output projection and remove some of the need
+	// for users to sling matricies themselves
+}
+
+static void wlr_gles3_end(struct wlr_renderer_state *state) {
+	// no-op
+}
+
+static struct wlr_surface *wlr_gles3_surface_init(struct wlr_renderer_state *state) {
+	return gles3_surface_init();
+}
+
+static bool wlr_gles3_render_surface(struct wlr_renderer_state *state,
+		struct wlr_surface *surface, const float (*matrix)[16]) {
+	assert(surface && surface->valid);
+	switch (surface->format) {
+	case GL_RGB:
+		glUseProgram(shaders.rgb);
+		break;
+	case GL_RGBA:
+		glUseProgram(shaders.rgba);
+		break;
+	default:
+		return false;
+	}
+	glBindVertexArray(vao);
+	glBindBuffer(GL_ARRAY_BUFFER, vbo);
+	glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, ebo);
+	wlr_surface_bind(surface);
+	glUniformMatrix4fv(0, 1, GL_TRUE, *matrix);
+	glDrawElements(GL_TRIANGLES, 6, GL_UNSIGNED_INT, 0);
+	return true;
+}
+
+static void wlr_gles3_destroy(struct wlr_renderer_state *state) {
+	// no-op
+}
+
+static struct wlr_renderer_impl wlr_renderer_impl = {
+	.begin = wlr_gles3_begin,
+	.end = wlr_gles3_end,
+	.surface_init = wlr_gles3_surface_init,
+	.render_with_matrix = wlr_gles3_render_surface,
+	.destroy = wlr_gles3_destroy
+};
+
+struct wlr_renderer *wlr_gles3_renderer_init() {
+	init_globals();
+	return wlr_renderer_init(NULL, &wlr_renderer_impl);
+}