feat(pandagl): update image reader to support reading one row of data

lib/pandagl/include/pandagl.h

@@ -20,6 +20,7 @@
 #include "pandagl/background.h"
 #include "pandagl/border.h"
 #include "pandagl/boxshadow.h"
+#include "pandagl/file_reader.h"
 #include "pandagl/font.h"
 #include "pandagl/text.h"
 #include "pandagl/image.h"

lib/pandagl/include/pandagl/file_reader.h

@@ -0,0 +1,40 @@
+
+#ifndef LIB_PANDAGL_INCLUDE_PANDAGL_FILE_READER_H
+#define LIB_PANDAGL_INCLUDE_PANDAGL_FILE_READER_H
+
+#include "common.h"
+#include "types.h"
+
+PD_BEGIN_DECLS
+
+typedef struct pd_file_reader_t {
+        void *stream_data;
+        void (*fn_close)(void*);
+        void (*fn_rewind)(void*);
+        size_t (*fn_read)(void *, void *, size_t);
+        void (*fn_skip)(void *, long);
+} pd_file_reader_t;
+
+PD_INLINE size_t pd_file_reader_read(pd_file_reader_t *reader, void *buffer,
+                                      size_t size)
+{
+        return reader->fn_read(reader->stream_data, buffer, size);
+}
+
+PD_INLINE void pd_file_reader_rewind(pd_file_reader_t *reader)
+{
+        reader->fn_rewind(reader->stream_data);
+}
+
+PD_INLINE void pd_file_reader_skip(pd_file_reader_t *reader, long bytes)
+{
+        reader->fn_skip(reader->stream_data, bytes);
+}
+
+PD_PUBLIC pd_file_reader_t *pd_file_reader_create(void);
+PD_PUBLIC pd_file_reader_t *pd_file_reader_create_from_file(const char *filename);
+PD_PUBLIC void pd_file_reader_destroy(pd_file_reader_t *reader);
+
+PD_END_DECLS
+
+#endif

lib/pandagl/include/pandagl/image.h

@@ -18,17 +18,12 @@
 
 PD_BEGIN_DECLS
 
-typedef void (*pd_image_progress_func_t)(void *, float);
-typedef size_t (*pd_image_read_func_t)(void *, void *, size_t);
-typedef void (*pd_image_skip_func_t)(void *, long);
-typedef void (*pd_image_func_t)(void *);
-
-/** 图像读取器的类型 */
 typedef enum pd_image_reader_type_t {
-	PD_UNKNOWN_READER,
-	PD_PNG_READER,
-	PD_JPEG_READER,
-	PD_BMP_READER
+        PD_UNKNOWN_READER,
+        PD_PNG_READER,
+        PD_JPEG_READER,
+        PD_BMP_READER,
+        PD_READER_COUNT
 } pd_image_reader_type_t;
 
 #define PD_UNKNOWN_IMAGE PD_UNKNOWN_READER
@@ -37,106 +32,47 @@ typedef enum pd_image_reader_type_t {
 #define PD_BMP_IMAGE PD_BMP_READER
 
 #define pd_image_reader_set_jump(READER) \
-	(READER)->env &&setjmp(*((READER)->env))
+        (READER)->env &&setjmp(*((READER)->env))
 
 typedef struct pd_image_header_t {
-	int type;
-	int bit_depth;
-	int color_type;
-	unsigned int width, height;
+        int type;
+        int bit_depth;
+        pd_color_type_t color_type;
+        unsigned int width, height;
 } pd_image_header_t;
 
-/** 图像读取器 */
 typedef struct pd_image_reader_t {
-	/** 自定义的输入流数据 */
-	void *stream_data;
-
-	/** 是否有错误 */
-	unsigned char has_error;
-
-	/** 图像头部信息 */
-	pd_image_header_t header;
-
-	/** 在开始读取前调用的函数 */
-	pd_image_func_t fn_begin;
-
-	/** 在结束读取时调用的函数 */
-	pd_image_func_t fn_end;
-
-	/** 游标重置函数，用于重置当前读取位置到数据流的开头处 */
-	pd_image_func_t fn_rewind;
-
-	/** 数据读取函数，用于从数据流中读取数据 */
-	pd_image_read_func_t fn_read;
-
-	/** 游标移动函数，用于跳过一段数据 */
-	pd_image_skip_func_t fn_skip;
-
-	/** 用于接收图像读取进度的函数 */
-	pd_image_progress_func_t fn_prog;
-
-	/** 接收图像读取进度时的附加参数 */
-	void *prog_arg;
-
-	/** 图片读取器类型 */
-	int type;
-
-	/** 私有数据 */
-	void *data;
-
-	/** 私有数据的析构函数 */
-	void (*destructor)(void *);
-
-	/** 堆栈环境缓存的指针，用于 setjump() */
-	jmp_buf *env;
-
-	/** 默认堆栈环境缓存 */
-	jmp_buf env_src;
+        char error_message[256];
+        pd_image_reader_type_t type;
+        pd_file_reader_t *file_reader;
+        pd_image_header_t header;
+        unsigned read_row_index;
+        unsigned pass;
+        unsigned passes;
+        void *reader_data;
 } pd_image_reader_t;
 
-/** 初始化适用于 PNG 图像的读取器 */
-PD_PUBLIC int pd_png_reader_init(pd_image_reader_t *reader);
+PD_PUBLIC pd_image_reader_t *pd_image_reader_create(void);
+PD_PUBLIC pd_image_reader_t *pd_image_reader_create_from_file(
+    const char *filename);
 
-/** 初始化适用于 JPEG 图像的读取器 */
-PD_PUBLIC int pd_jpeg_reader_init(pd_image_reader_t *reader);
-
-/** 初始化适用于 BMP 图像的读取器 */
-PD_PUBLIC int pd_bmp_reader_init(pd_image_reader_t *reader);
-
-PD_PUBLIC void pd_image_reader_set_file(pd_image_reader_t *reader, FILE *fp);
-
-/** 创建图像读取器 */
-PD_PUBLIC int pd_image_reader_init(pd_image_reader_t *reader);
-
-/** 销毁图像读取器 */
 PD_PUBLIC void pd_image_reader_destroy(pd_image_reader_t *reader);
-
-PD_PUBLIC int pd_png_reader_read_header(pd_image_reader_t *reader);
-
-PD_PUBLIC int pd_jpeg_reader_read_header(pd_image_reader_t *reader);
-
-PD_PUBLIC int pd_bmp_reader_read_header(pd_image_reader_t *reader);
-
-PD_PUBLIC int pd_image_reader_read_header(pd_image_reader_t *reader);
-
-PD_PUBLIC int pd_png_reader_read_data(pd_image_reader_t *reader,
-				     pd_canvas_t *graph);
-
-PD_PUBLIC int pd_bmp_reader_read_data(pd_image_reader_t *reader,
-				     pd_canvas_t *graph);
-
-PD_PUBLIC int pd_image_reader_read_data(pd_image_reader_t *reader,
-				       pd_canvas_t *graph);
-
-/** 将图像数据写入至png文件 */
-PD_PUBLIC int pd_write_png_file(const char *file_name, const pd_canvas_t *graph);
-
-/** 载入指定图片文件的图像数据 */
-PD_PUBLIC int pd_read_image_from_file(const char *filepath, pd_canvas_t *out);
-
-/** 从文件中获取图像尺寸 */
-PD_PUBLIC int pd_read_image_size_from_file(const char *filepath, int *width,
-					  int *height);
+PD_PUBLIC jmp_buf *pd_image_reader_jmpbuf(pd_image_reader_t *reader);
+PD_PUBLIC pd_error_t pd_image_reader_read_header(pd_image_reader_t *reader);
+PD_PUBLIC void pd_image_reader_start(pd_image_reader_t *reader);
+PD_PUBLIC pd_error_t pd_image_reader_create_buffer(pd_image_reader_t *reader,
+                                                   pd_canvas_t *out);
+PD_PUBLIC void pd_image_reader_read_row(pd_image_reader_t *reader,
+                                        pd_canvas_t *data);
+PD_PUBLIC void pd_image_reader_finish(pd_image_reader_t *reader);
+PD_PUBLIC pd_error_t pd_image_reader_read_data(pd_image_reader_t *reader,
+                                               pd_canvas_t *out);
+
+PD_PUBLIC pd_error_t pd_read_image_from_file(const char *filepath,
+                                             pd_canvas_t *out);
+
+PD_PUBLIC int pd_write_png_file(const char *file_name,
+                                const pd_canvas_t *graph);
 
 PD_END_DECLS
 

lib/pandagl/include/pandagl/types.h

@@ -21,14 +21,15 @@ typedef unsigned char pd_bool_t;
 #define PD_TRUE 1
 
 typedef enum pd_color_type_t {
+	PD_COLOR_TYPE_UNSUPPORTED,
 	PD_COLOR_TYPE_INDEX8,   /**< 8位索引 */
 	PD_COLOR_TYPE_GRAY8,    /**< 8位灰度 */
 	PD_COLOR_TYPE_RGB323,   /**< RGB323 */
 	PD_COLOR_TYPE_ARGB2222, /**< ARGB2222 */
 	PD_COLOR_TYPE_RGB555,   /**< RGB555 */
 	PD_COLOR_TYPE_RGB565,   /**< RGB565 */
 	PD_COLOR_TYPE_RGB888,   /**< RGB888 */
-	PD_COLOR_TYPE_ARGB8888  /**< RGB8888 */
+	PD_COLOR_TYPE_ARGB8888,  /**< RGB8888 */
 } pd_color_type_t;
 
 #define PD_COLOR_TYPE_RGB PD_COLOR_TYPE_RGB888
@@ -126,4 +127,14 @@ typedef struct pd_border_t {
 	unsigned int bottom_right_radius;
 } pd_border_t;
 
+typedef enum pd_error_t {
+	PD_OK = 0,
+	PD_ERROR_NOT_FOUND,
+	PD_ERROR_NOT_IMPLEMENTED,
+	PD_ERROR_IMAGE_HEADER_INVALID,
+	PD_ERROR_IMAGE_TYPE_INCORRECT,
+	PD_ERROR_IMAGE_DATA_NOT_SUPPORTED,
+	PD_ERROR_IMAGE_READING
+} pd_error_t;
+
 #endif

lib/pandagl/src/file_reader.c

@@ -0,0 +1,52 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <pandagl/file_reader.h>
+
+static size_t pd_file_stream_on_read(void *data, void *buffer, size_t size)
+{
+        return fread(buffer, 1, size, data);
+}
+
+static void pd_file_stream_on_skip(void *data, long offset)
+{
+        fseek(data, offset, SEEK_CUR);
+}
+
+static void pd_file_stream_on_rewind(void *data)
+{
+        rewind(data);
+}
+
+static void pd_file_stream_on_close(void *data)
+{
+        fclose(data);
+}
+
+pd_file_reader_t *pd_file_reader_create(void)
+{
+	return calloc(1, sizeof(pd_file_reader_t));
+}
+
+pd_file_reader_t *pd_file_reader_create_from_file(const char *filename)
+{
+        FILE *fp;
+        pd_file_reader_t *reader;
+
+        fp = fopen(filename, "rb");
+	if (fp == NULL) {
+		return NULL;
+	}
+	reader = pd_file_reader_create();
+        reader->stream_data = fp;
+        reader->fn_skip = pd_file_stream_on_skip;
+        reader->fn_read = pd_file_stream_on_read;
+        reader->fn_rewind = pd_file_stream_on_rewind;
+        reader->fn_close = pd_file_stream_on_close;
+	return reader;
+}
+
+void pd_file_reader_destroy(pd_file_reader_t *reader)
+{
+	reader->fn_close(reader->stream_data);
+	free(reader);
+}