1 files changed, 100 insertions, 0 deletions
diff --git a/render/shader.c b/render/shader.c
new file mode 100644
index 00000000..d7c10614
--- /dev/null
+++ b/render/shader.c
@@ -0,0 +1,100 @@
+#include <assert.h>
+#include <string.h>
+#include <stdlib.h>
+#include <stdint.h>
+#include <stdbool.h>
+#include <GLES3/gl3.h>
+#include <wlr/render.h>
+#include <wlr/render/matrix.h>
+#include <wayland-util.h>
+#include "render.h"
+
+static bool create_shader(GLenum type, const GLchar *src, GLint len, GLuint *shader) {
+	*shader = glCreateShader(type);
+	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;
+}
+
+struct wlr_shader *wlr_shader_init(const char *vertex) {
+	struct wlr_shader *shader = calloc(sizeof(struct wlr_shader), 1);
+	if (!create_shader(GL_VERTEX_SHADER, vertex, strlen(vertex), &shader->vert)) {
+		wlr_shader_destroy(shader);
+		return NULL;
+	}
+	return shader;
+}
+
+bool wlr_shader_add_format(struct wlr_shader *shader, uint32_t format,
+		const char *frag) {
+	assert(shader);
+	struct wlr_shader *_shader = shader;
+	if (_shader->valid) {
+		shader = calloc(sizeof(struct wlr_shader), 1);
+		shader->vert = _shader->vert;
+	}
+	shader->format = format;
+	GLuint _frag;
+	if (!create_shader(GL_FRAGMENT_SHADER, frag, strlen(frag), &_frag)) {
+		goto error;
+	}
+	shader->program = glCreateProgram();
+	glAttachShader(shader->program, shader->vert);
+	glAttachShader(shader->program, _frag);
+	glLinkProgram(shader->program);
+	glDeleteProgram(_frag);
+	if (!_shader->valid) {
+		_shader->valid = true;
+	} else {
+		wl_list_insert(&_shader->link, &shader->link);
+	}
+	return true;
+error:
+	if (_shader->valid) {
+		wlr_shader_destroy(shader);
+	}
+	return false;
+}
+
+bool wlr_shader_use(struct wlr_shader *shader, uint32_t format) {
+	struct wlr_shader *s = shader;
+	if (s->format == format) {
+		glUseProgram(s->program);
+		return true;
+	}
+	if (shader->link.next) {
+		wl_list_for_each(s, &shader->link, link) {
+			if (s->format == format) {
+				glUseProgram(s->program);
+				return true;
+			}
+		}
+	}
+	return false;
+}
+
+void wlr_shader_destroy(struct wlr_shader *shader) {
+	if (!shader) {
+		return;
+	}
+	glDeleteProgram(shader->vert);
+	glDeleteProgram(shader->program);
+	if (shader->link.next) {
+		struct wlr_shader *next = wl_container_of(shader->link.next,
+				next, link);
+		wlr_shader_destroy(next);
+	}
+	free(shader);
+}