From f1cfe964a865974cc77e54b777ab462b63a489d8 Mon Sep 17 00:00:00 2001 From: hippoz Date: Mon, 3 Jul 2023 15:20:06 +0300 Subject: [PATCH] add texture --- assets/fish.qoi | Bin 0 -> 1863 bytes src/main.cpp | 36 ++- src/vendor/qoi.h | 649 +++++++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 678 insertions(+), 7 deletions(-) create mode 100644 assets/fish.qoi create mode 100644 src/vendor/qoi.h diff --git a/assets/fish.qoi b/assets/fish.qoi new file mode 100644 index 0000000000000000000000000000000000000000..6c416971fa47935e8b85fe99f3f8af6c4ced5695 GIT binary patch literal 1863 zcmcIlU1(fI6h3!DOroCFShz1q-~O7OG}IKMT(-;rwhIc zf=_BqN`3QHeBZmf*}tTl#7M2QQo*!ak~Ev9t!XUmS$^ zgfih4?7TB9Sp=*JF2pKG1kl|K`*VOAf3b#Ynn@hG#qMj)Lae8SDlhVag2qdFn#IZ@ zw3Nnb54NUq%HXPiz7+OZ3h~D%A?I=K9(j&*_;Do^o((-3PN1T?#0U4aV$xCV3{|2 zsETgRabF!x(9xY<3X8rwHA@E1_aF-fuchehP?SSX;tVa0B+aQ9tJu+z_9uOI+u&mPzr{eNj?OD_xND5Yt(u-NiS~$QW2ov4<@j_*Vcr_ zpYv#g!xTq(F|q?J+cB$fR+fC7voe2tJw|;V(2I`%Egeo`?aZK%e3Xe~QNj}jSYeNI zl9)fN`CV*IzE3rl{SX@;+3C^RktAntgbqFJ(W#6_R}LkpeZrTs)qqv5@|-mk>w7*n z(^P&dMoG5*jO%^tXc9~5kWM}mq1}%HeX}PTL(%EdwQA=boX^;&1R`x4V6%@te%_;0 z6zEG65fz1WoIcD%Xy4;NpA1B3ow>Q0tff7Cb0SGN=3RiSW@3!K*d38f9^?SlIhfS9 zyO_eG&tHgadjbo5n7blowSgkX(@fI$uS5;~@M?4imG;Nz(?O5Mc6fC6xSw>D%ev-q zr^6j9Za2x@!aH$8`vTz6^N?(wkAD5sBWU$GWxx_lr`!)cFxdL#BEPW9xb z<>ol8e2KBf`0FVw^8sJ$Zq=P{VQk78wz?U)$><6FI!N|0R@H@WD&S3-l|Zy4Y^ z0V|e8ikXLb<>OMn(Aq)v%Q+twe5+jN;I>`v@J*A03rY$R;9}SR9m5T$;i6O}Fl=!} z`%dm(2D@D+w3oH>ffsZLB^65XV8h(kS0X9kB11tHpd_rY$%4av?evO|DpMGyC^$fS ztGnHS5O;sNtG=Vk474kOEc2yabKeMAgr+V-dsYNX2J`%J$ywyezh4=FKbQ|&d!9Yn GpZ5 - +#define QOI_IMPLEMENTATION +#include "vendor/qoi.h" unsigned int create_shader(unsigned int type, const char **source) { @@ -69,6 +70,10 @@ void framebuffer_size_callback(GLFWwindow *window, int width, int height) int main() { + qoi_desc fish_desc; + void *fish_rgba = qoi_read("assets/fish.qoi", &fish_desc, 4); + + if (!glfwInit()) { return 1; } @@ -90,33 +95,45 @@ int main() float verts[] = { - 0.0f, 0.5f, 1.0f, 0.0f, 0.0f, - -0.5f, -0.5f, 0.0f, 1.0f, 0.0f, - 0.5f, -0.5f, 0.0f, 0.0f, 1.0f, + // position // color // texture coords + 0.0f, 0.5f, 1.0f, 0.0f, 0.0f, 0.5f, 1.0f, + -0.5f, -0.5f, 0.0f, 1.0f, 0.0f, 0.0f, 0.0f, + 0.5f, -0.5f, 0.0f, 0.0f, 1.0f, 1.0f, 0.0f, }; static const char *vertex_shader_source = "" "#version 330 core\n" "layout (location = 0) in vec2 aPos;\n" "layout (location = 1) in vec3 aColor;\n" + "layout (location = 2) in vec2 aTexCoord;\n" "out vec3 fragColor;\n" + "out vec2 TexCoord;\n" "void main()\n" "{\n" " gl_Position = vec4(aPos.x, aPos.y, 0.0, 1.0);\n" " fragColor = aColor;\n" + " TexCoord = aTexCoord;\n" "}\0"; static const char *fragment_shader_source = "" "#version 330 core\n" "in vec3 fragColor;\n" + "in vec2 TexCoord;\n" "out vec4 FragColor;\n" + "uniform sampler2D tex;\n" "void main()\n" "{\n" - " FragColor = vec4(fragColor, 1.0f);\n" + " FragColor = texture(tex, TexCoord);\n" "}\0"; unsigned int program = create_program(vertex_shader_source, fragment_shader_source); + unsigned int texture; + glGenTextures(1, &texture); + glBindTexture(GL_TEXTURE_2D, texture); + glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, fish_desc.width, fish_desc.height, 0, GL_RGBA, GL_UNSIGNED_BYTE, fish_rgba); + glGenerateMipmap(GL_TEXTURE_2D); + unsigned int vertex_array; glGenVertexArrays(1, &vertex_array); glBindVertexArray(vertex_array); @@ -127,18 +144,23 @@ int main() glBufferData(GL_ARRAY_BUFFER, sizeof(verts), &verts, GL_STATIC_DRAW); // 2D position - glVertexAttribPointer(0, 2, GL_FLOAT, GL_FALSE, 5 * sizeof(float), (const void*)0); + glVertexAttribPointer(0, 2, GL_FLOAT, GL_FALSE, 7 * sizeof(float), (const void*)0); glEnableVertexAttribArray(0); // RGB color - glVertexAttribPointer(1, 3, GL_FLOAT, GL_FALSE, 5 * sizeof(float), (const void*)(2 * sizeof(float))); + glVertexAttribPointer(1, 3, GL_FLOAT, GL_FALSE, 7 * sizeof(float), (const void*)(2 * sizeof(float))); glEnableVertexAttribArray(1); + // texture coords + glVertexAttribPointer(2, 2, GL_FLOAT, GL_FALSE, 7 * sizeof(float), (const void*)(5 * sizeof(float))); + glEnableVertexAttribArray(2); + while (!glfwWindowShouldClose(window)) { glClearColor(0.5, 0.5, 0.5, 1.0); glClear(GL_COLOR_BUFFER_BIT); glUseProgram(program); + glBindTexture(GL_TEXTURE_2D, texture); glBindVertexArray(vertex_array); glDrawArrays(GL_TRIANGLES, 0, 3); diff --git a/src/vendor/qoi.h b/src/vendor/qoi.h new file mode 100644 index 0000000..f2800b0 --- /dev/null +++ b/src/vendor/qoi.h @@ -0,0 +1,649 @@ +/* + +Copyright (c) 2021, Dominic Szablewski - https://phoboslab.org +SPDX-License-Identifier: MIT + + +QOI - The "Quite OK Image" format for fast, lossless image compression + +-- About + +QOI encodes and decodes images in a lossless format. Compared to stb_image and +stb_image_write QOI offers 20x-50x faster encoding, 3x-4x faster decoding and +20% better compression. + + +-- Synopsis + +// Define `QOI_IMPLEMENTATION` in *one* C/C++ file before including this +// library to create the implementation. + +#define QOI_IMPLEMENTATION +#include "qoi.h" + +// Encode and store an RGBA buffer to the file system. The qoi_desc describes +// the input pixel data. +qoi_write("image_new.qoi", rgba_pixels, &(qoi_desc){ + .width = 1920, + .height = 1080, + .channels = 4, + .colorspace = QOI_SRGB +}); + +// Load and decode a QOI image from the file system into a 32bbp RGBA buffer. +// The qoi_desc struct will be filled with the width, height, number of channels +// and colorspace read from the file header. +qoi_desc desc; +void *rgba_pixels = qoi_read("image.qoi", &desc, 4); + + + +-- Documentation + +This library provides the following functions; +- qoi_read -- read and decode a QOI file +- qoi_decode -- decode the raw bytes of a QOI image from memory +- qoi_write -- encode and write a QOI file +- qoi_encode -- encode an rgba buffer into a QOI image in memory + +See the function declaration below for the signature and more information. + +If you don't want/need the qoi_read and qoi_write functions, you can define +QOI_NO_STDIO before including this library. + +This library uses malloc() and free(). To supply your own malloc implementation +you can define QOI_MALLOC and QOI_FREE before including this library. + +This library uses memset() to zero-initialize the index. To supply your own +implementation you can define QOI_ZEROARR before including this library. + + +-- Data Format + +A QOI file has a 14 byte header, followed by any number of data "chunks" and an +8-byte end marker. + +struct qoi_header_t { + char magic[4]; // magic bytes "qoif" + uint32_t width; // image width in pixels (BE) + uint32_t height; // image height in pixels (BE) + uint8_t channels; // 3 = RGB, 4 = RGBA + uint8_t colorspace; // 0 = sRGB with linear alpha, 1 = all channels linear +}; + +Images are encoded row by row, left to right, top to bottom. The decoder and +encoder start with {r: 0, g: 0, b: 0, a: 255} as the previous pixel value. An +image is complete when all pixels specified by width * height have been covered. + +Pixels are encoded as + - a run of the previous pixel + - an index into an array of previously seen pixels + - a difference to the previous pixel value in r,g,b + - full r,g,b or r,g,b,a values + +The color channels are assumed to not be premultiplied with the alpha channel +("un-premultiplied alpha"). + +A running array[64] (zero-initialized) of previously seen pixel values is +maintained by the encoder and decoder. Each pixel that is seen by the encoder +and decoder is put into this array at the position formed by a hash function of +the color value. In the encoder, if the pixel value at the index matches the +current pixel, this index position is written to the stream as QOI_OP_INDEX. +The hash function for the index is: + + index_position = (r * 3 + g * 5 + b * 7 + a * 11) % 64 + +Each chunk starts with a 2- or 8-bit tag, followed by a number of data bits. The +bit length of chunks is divisible by 8 - i.e. all chunks are byte aligned. All +values encoded in these data bits have the most significant bit on the left. + +The 8-bit tags have precedence over the 2-bit tags. A decoder must check for the +presence of an 8-bit tag first. + +The byte stream's end is marked with 7 0x00 bytes followed a single 0x01 byte. + + +The possible chunks are: + + +.- QOI_OP_INDEX ----------. +| Byte[0] | +| 7 6 5 4 3 2 1 0 | +|-------+-----------------| +| 0 0 | index | +`-------------------------` +2-bit tag b00 +6-bit index into the color index array: 0..63 + +A valid encoder must not issue 2 or more consecutive QOI_OP_INDEX chunks to the +same index. QOI_OP_RUN should be used instead. + + +.- QOI_OP_DIFF -----------. +| Byte[0] | +| 7 6 5 4 3 2 1 0 | +|-------+-----+-----+-----| +| 0 1 | dr | dg | db | +`-------------------------` +2-bit tag b01 +2-bit red channel difference from the previous pixel between -2..1 +2-bit green channel difference from the previous pixel between -2..1 +2-bit blue channel difference from the previous pixel between -2..1 + +The difference to the current channel values are using a wraparound operation, +so "1 - 2" will result in 255, while "255 + 1" will result in 0. + +Values are stored as unsigned integers with a bias of 2. E.g. -2 is stored as +0 (b00). 1 is stored as 3 (b11). + +The alpha value remains unchanged from the previous pixel. + + +.- QOI_OP_LUMA -------------------------------------. +| Byte[0] | Byte[1] | +| 7 6 5 4 3 2 1 0 | 7 6 5 4 3 2 1 0 | +|-------+-----------------+-------------+-----------| +| 1 0 | green diff | dr - dg | db - dg | +`---------------------------------------------------` +2-bit tag b10 +6-bit green channel difference from the previous pixel -32..31 +4-bit red channel difference minus green channel difference -8..7 +4-bit blue channel difference minus green channel difference -8..7 + +The green channel is used to indicate the general direction of change and is +encoded in 6 bits. The red and blue channels (dr and db) base their diffs off +of the green channel difference and are encoded in 4 bits. I.e.: + dr_dg = (cur_px.r - prev_px.r) - (cur_px.g - prev_px.g) + db_dg = (cur_px.b - prev_px.b) - (cur_px.g - prev_px.g) + +The difference to the current channel values are using a wraparound operation, +so "10 - 13" will result in 253, while "250 + 7" will result in 1. + +Values are stored as unsigned integers with a bias of 32 for the green channel +and a bias of 8 for the red and blue channel. + +The alpha value remains unchanged from the previous pixel. + + +.- QOI_OP_RUN ------------. +| Byte[0] | +| 7 6 5 4 3 2 1 0 | +|-------+-----------------| +| 1 1 | run | +`-------------------------` +2-bit tag b11 +6-bit run-length repeating the previous pixel: 1..62 + +The run-length is stored with a bias of -1. Note that the run-lengths 63 and 64 +(b111110 and b111111) are illegal as they are occupied by the QOI_OP_RGB and +QOI_OP_RGBA tags. + + +.- QOI_OP_RGB ------------------------------------------. +| Byte[0] | Byte[1] | Byte[2] | Byte[3] | +| 7 6 5 4 3 2 1 0 | 7 .. 0 | 7 .. 0 | 7 .. 0 | +|-------------------------+---------+---------+---------| +| 1 1 1 1 1 1 1 0 | red | green | blue | +`-------------------------------------------------------` +8-bit tag b11111110 +8-bit red channel value +8-bit green channel value +8-bit blue channel value + +The alpha value remains unchanged from the previous pixel. + + +.- QOI_OP_RGBA ---------------------------------------------------. +| Byte[0] | Byte[1] | Byte[2] | Byte[3] | Byte[4] | +| 7 6 5 4 3 2 1 0 | 7 .. 0 | 7 .. 0 | 7 .. 0 | 7 .. 0 | +|-------------------------+---------+---------+---------+---------| +| 1 1 1 1 1 1 1 1 | red | green | blue | alpha | +`-----------------------------------------------------------------` +8-bit tag b11111111 +8-bit red channel value +8-bit green channel value +8-bit blue channel value +8-bit alpha channel value + +*/ + + +/* ----------------------------------------------------------------------------- +Header - Public functions */ + +#ifndef QOI_H +#define QOI_H + +#ifdef __cplusplus +extern "C" { +#endif + +/* A pointer to a qoi_desc struct has to be supplied to all of qoi's functions. +It describes either the input format (for qoi_write and qoi_encode), or is +filled with the description read from the file header (for qoi_read and +qoi_decode). + +The colorspace in this qoi_desc is an enum where + 0 = sRGB, i.e. gamma scaled RGB channels and a linear alpha channel + 1 = all channels are linear +You may use the constants QOI_SRGB or QOI_LINEAR. The colorspace is purely +informative. It will be saved to the file header, but does not affect +how chunks are en-/decoded. */ + +#define QOI_SRGB 0 +#define QOI_LINEAR 1 + +typedef struct { + unsigned int width; + unsigned int height; + unsigned char channels; + unsigned char colorspace; +} qoi_desc; + +#ifndef QOI_NO_STDIO + +/* Encode raw RGB or RGBA pixels into a QOI image and write it to the file +system. The qoi_desc struct must be filled with the image width, height, +number of channels (3 = RGB, 4 = RGBA) and the colorspace. + +The function returns 0 on failure (invalid parameters, or fopen or malloc +failed) or the number of bytes written on success. */ + +int qoi_write(const char *filename, const void *data, const qoi_desc *desc); + + +/* Read and decode a QOI image from the file system. If channels is 0, the +number of channels from the file header is used. If channels is 3 or 4 the +output format will be forced into this number of channels. + +The function either returns NULL on failure (invalid data, or malloc or fopen +failed) or a pointer to the decoded pixels. On success, the qoi_desc struct +will be filled with the description from the file header. + +The returned pixel data should be free()d after use. */ + +void *qoi_read(const char *filename, qoi_desc *desc, int channels); + +#endif /* QOI_NO_STDIO */ + + +/* Encode raw RGB or RGBA pixels into a QOI image in memory. + +The function either returns NULL on failure (invalid parameters or malloc +failed) or a pointer to the encoded data on success. On success the out_len +is set to the size in bytes of the encoded data. + +The returned qoi data should be free()d after use. */ + +void *qoi_encode(const void *data, const qoi_desc *desc, int *out_len); + + +/* Decode a QOI image from memory. + +The function either returns NULL on failure (invalid parameters or malloc +failed) or a pointer to the decoded pixels. On success, the qoi_desc struct +is filled with the description from the file header. + +The returned pixel data should be free()d after use. */ + +void *qoi_decode(const void *data, int size, qoi_desc *desc, int channels); + + +#ifdef __cplusplus +} +#endif +#endif /* QOI_H */ + + +/* ----------------------------------------------------------------------------- +Implementation */ + +#ifdef QOI_IMPLEMENTATION +#include +#include + +#ifndef QOI_MALLOC + #define QOI_MALLOC(sz) malloc(sz) + #define QOI_FREE(p) free(p) +#endif +#ifndef QOI_ZEROARR + #define QOI_ZEROARR(a) memset((a),0,sizeof(a)) +#endif + +#define QOI_OP_INDEX 0x00 /* 00xxxxxx */ +#define QOI_OP_DIFF 0x40 /* 01xxxxxx */ +#define QOI_OP_LUMA 0x80 /* 10xxxxxx */ +#define QOI_OP_RUN 0xc0 /* 11xxxxxx */ +#define QOI_OP_RGB 0xfe /* 11111110 */ +#define QOI_OP_RGBA 0xff /* 11111111 */ + +#define QOI_MASK_2 0xc0 /* 11000000 */ + +#define QOI_COLOR_HASH(C) (C.rgba.r*3 + C.rgba.g*5 + C.rgba.b*7 + C.rgba.a*11) +#define QOI_MAGIC \ + (((unsigned int)'q') << 24 | ((unsigned int)'o') << 16 | \ + ((unsigned int)'i') << 8 | ((unsigned int)'f')) +#define QOI_HEADER_SIZE 14 + +/* 2GB is the max file size that this implementation can safely handle. We guard +against anything larger than that, assuming the worst case with 5 bytes per +pixel, rounded down to a nice clean value. 400 million pixels ought to be +enough for anybody. */ +#define QOI_PIXELS_MAX ((unsigned int)400000000) + +typedef union { + struct { unsigned char r, g, b, a; } rgba; + unsigned int v; +} qoi_rgba_t; + +static const unsigned char qoi_padding[8] = {0,0,0,0,0,0,0,1}; + +static void qoi_write_32(unsigned char *bytes, int *p, unsigned int v) { + bytes[(*p)++] = (0xff000000 & v) >> 24; + bytes[(*p)++] = (0x00ff0000 & v) >> 16; + bytes[(*p)++] = (0x0000ff00 & v) >> 8; + bytes[(*p)++] = (0x000000ff & v); +} + +static unsigned int qoi_read_32(const unsigned char *bytes, int *p) { + unsigned int a = bytes[(*p)++]; + unsigned int b = bytes[(*p)++]; + unsigned int c = bytes[(*p)++]; + unsigned int d = bytes[(*p)++]; + return a << 24 | b << 16 | c << 8 | d; +} + +void *qoi_encode(const void *data, const qoi_desc *desc, int *out_len) { + int i, max_size, p, run; + int px_len, px_end, px_pos, channels; + unsigned char *bytes; + const unsigned char *pixels; + qoi_rgba_t index[64]; + qoi_rgba_t px, px_prev; + + if ( + data == NULL || out_len == NULL || desc == NULL || + desc->width == 0 || desc->height == 0 || + desc->channels < 3 || desc->channels > 4 || + desc->colorspace > 1 || + desc->height >= QOI_PIXELS_MAX / desc->width + ) { + return NULL; + } + + max_size = + desc->width * desc->height * (desc->channels + 1) + + QOI_HEADER_SIZE + sizeof(qoi_padding); + + p = 0; + bytes = (unsigned char *) QOI_MALLOC(max_size); + if (!bytes) { + return NULL; + } + + qoi_write_32(bytes, &p, QOI_MAGIC); + qoi_write_32(bytes, &p, desc->width); + qoi_write_32(bytes, &p, desc->height); + bytes[p++] = desc->channels; + bytes[p++] = desc->colorspace; + + + pixels = (const unsigned char *)data; + + QOI_ZEROARR(index); + + run = 0; + px_prev.rgba.r = 0; + px_prev.rgba.g = 0; + px_prev.rgba.b = 0; + px_prev.rgba.a = 255; + px = px_prev; + + px_len = desc->width * desc->height * desc->channels; + px_end = px_len - desc->channels; + channels = desc->channels; + + for (px_pos = 0; px_pos < px_len; px_pos += channels) { + px.rgba.r = pixels[px_pos + 0]; + px.rgba.g = pixels[px_pos + 1]; + px.rgba.b = pixels[px_pos + 2]; + + if (channels == 4) { + px.rgba.a = pixels[px_pos + 3]; + } + + if (px.v == px_prev.v) { + run++; + if (run == 62 || px_pos == px_end) { + bytes[p++] = QOI_OP_RUN | (run - 1); + run = 0; + } + } + else { + int index_pos; + + if (run > 0) { + bytes[p++] = QOI_OP_RUN | (run - 1); + run = 0; + } + + index_pos = QOI_COLOR_HASH(px) % 64; + + if (index[index_pos].v == px.v) { + bytes[p++] = QOI_OP_INDEX | index_pos; + } + else { + index[index_pos] = px; + + if (px.rgba.a == px_prev.rgba.a) { + signed char vr = px.rgba.r - px_prev.rgba.r; + signed char vg = px.rgba.g - px_prev.rgba.g; + signed char vb = px.rgba.b - px_prev.rgba.b; + + signed char vg_r = vr - vg; + signed char vg_b = vb - vg; + + if ( + vr > -3 && vr < 2 && + vg > -3 && vg < 2 && + vb > -3 && vb < 2 + ) { + bytes[p++] = QOI_OP_DIFF | (vr + 2) << 4 | (vg + 2) << 2 | (vb + 2); + } + else if ( + vg_r > -9 && vg_r < 8 && + vg > -33 && vg < 32 && + vg_b > -9 && vg_b < 8 + ) { + bytes[p++] = QOI_OP_LUMA | (vg + 32); + bytes[p++] = (vg_r + 8) << 4 | (vg_b + 8); + } + else { + bytes[p++] = QOI_OP_RGB; + bytes[p++] = px.rgba.r; + bytes[p++] = px.rgba.g; + bytes[p++] = px.rgba.b; + } + } + else { + bytes[p++] = QOI_OP_RGBA; + bytes[p++] = px.rgba.r; + bytes[p++] = px.rgba.g; + bytes[p++] = px.rgba.b; + bytes[p++] = px.rgba.a; + } + } + } + px_prev = px; + } + + for (i = 0; i < (int)sizeof(qoi_padding); i++) { + bytes[p++] = qoi_padding[i]; + } + + *out_len = p; + return bytes; +} + +void *qoi_decode(const void *data, int size, qoi_desc *desc, int channels) { + const unsigned char *bytes; + unsigned int header_magic; + unsigned char *pixels; + qoi_rgba_t index[64]; + qoi_rgba_t px; + int px_len, chunks_len, px_pos; + int p = 0, run = 0; + + if ( + data == NULL || desc == NULL || + (channels != 0 && channels != 3 && channels != 4) || + size < QOI_HEADER_SIZE + (int)sizeof(qoi_padding) + ) { + return NULL; + } + + bytes = (const unsigned char *)data; + + header_magic = qoi_read_32(bytes, &p); + desc->width = qoi_read_32(bytes, &p); + desc->height = qoi_read_32(bytes, &p); + desc->channels = bytes[p++]; + desc->colorspace = bytes[p++]; + + if ( + desc->width == 0 || desc->height == 0 || + desc->channels < 3 || desc->channels > 4 || + desc->colorspace > 1 || + header_magic != QOI_MAGIC || + desc->height >= QOI_PIXELS_MAX / desc->width + ) { + return NULL; + } + + if (channels == 0) { + channels = desc->channels; + } + + px_len = desc->width * desc->height * channels; + pixels = (unsigned char *) QOI_MALLOC(px_len); + if (!pixels) { + return NULL; + } + + QOI_ZEROARR(index); + px.rgba.r = 0; + px.rgba.g = 0; + px.rgba.b = 0; + px.rgba.a = 255; + + chunks_len = size - (int)sizeof(qoi_padding); + for (px_pos = 0; px_pos < px_len; px_pos += channels) { + if (run > 0) { + run--; + } + else if (p < chunks_len) { + int b1 = bytes[p++]; + + if (b1 == QOI_OP_RGB) { + px.rgba.r = bytes[p++]; + px.rgba.g = bytes[p++]; + px.rgba.b = bytes[p++]; + } + else if (b1 == QOI_OP_RGBA) { + px.rgba.r = bytes[p++]; + px.rgba.g = bytes[p++]; + px.rgba.b = bytes[p++]; + px.rgba.a = bytes[p++]; + } + else if ((b1 & QOI_MASK_2) == QOI_OP_INDEX) { + px = index[b1]; + } + else if ((b1 & QOI_MASK_2) == QOI_OP_DIFF) { + px.rgba.r += ((b1 >> 4) & 0x03) - 2; + px.rgba.g += ((b1 >> 2) & 0x03) - 2; + px.rgba.b += ( b1 & 0x03) - 2; + } + else if ((b1 & QOI_MASK_2) == QOI_OP_LUMA) { + int b2 = bytes[p++]; + int vg = (b1 & 0x3f) - 32; + px.rgba.r += vg - 8 + ((b2 >> 4) & 0x0f); + px.rgba.g += vg; + px.rgba.b += vg - 8 + (b2 & 0x0f); + } + else if ((b1 & QOI_MASK_2) == QOI_OP_RUN) { + run = (b1 & 0x3f); + } + + index[QOI_COLOR_HASH(px) % 64] = px; + } + + pixels[px_pos + 0] = px.rgba.r; + pixels[px_pos + 1] = px.rgba.g; + pixels[px_pos + 2] = px.rgba.b; + + if (channels == 4) { + pixels[px_pos + 3] = px.rgba.a; + } + } + + return pixels; +} + +#ifndef QOI_NO_STDIO +#include + +int qoi_write(const char *filename, const void *data, const qoi_desc *desc) { + FILE *f = fopen(filename, "wb"); + int size, err; + void *encoded; + + if (!f) { + return 0; + } + + encoded = qoi_encode(data, desc, &size); + if (!encoded) { + fclose(f); + return 0; + } + + fwrite(encoded, 1, size, f); + fflush(f); + err = ferror(f); + fclose(f); + + QOI_FREE(encoded); + return err ? 0 : size; +} + +void *qoi_read(const char *filename, qoi_desc *desc, int channels) { + FILE *f = fopen(filename, "rb"); + int size, bytes_read; + void *pixels, *data; + + if (!f) { + return NULL; + } + + fseek(f, 0, SEEK_END); + size = ftell(f); + if (size <= 0 || fseek(f, 0, SEEK_SET) != 0) { + fclose(f); + return NULL; + } + + data = QOI_MALLOC(size); + if (!data) { + fclose(f); + return NULL; + } + + bytes_read = fread(data, 1, size, f); + fclose(f); + pixels = (bytes_read != size) ? NULL : qoi_decode(data, bytes_read, desc, channels); + QOI_FREE(data); + return pixels; +} + +#endif /* QOI_NO_STDIO */ +#endif /* QOI_IMPLEMENTATION */