1. Start VS. Open C:\\CPP\\a998engine\\p_windows\\p_windows.sln<\/em><\/p>\n\n\n\n MyColor class<\/strong><\/p>\n\n\n\n The reason to have it as a separate class, is that we will need to keep colors in THREE different formats:<\/p>\n\n\n\n Any change to either of these formats must be reflected in the other two.<\/p>\n\n\n\n 2. Under xEngine <\/em>add new header (.h) file MyColor.h<\/strong><\/p>\n\n\n\n Location – C:\\CPP\\engine<\/em><\/p>\n\n\n\n Code:<\/p>\n\n\n <\/p>\n\n\n\n 3. Open platform.h<\/em> and replace code by following:<\/p>\n\n\n <\/p>\n\n\n\n 4. Under xEngine <\/em>add new C++ File (.cpp) file MyColor.cpp<\/strong><\/p>\n\n\n\n Location – C:\\CPP\\engine<\/em><\/p>\n\n\n\n Code:<\/p>\n\n\n <\/p>\n\n\n\n Material class<\/strong><\/p>\n\n\n\n “Material” in our case is an instruction HOW to render, which shader to use, which textures and colors, etc. For example, “Draw green surface with ucolor_flat shader” is one Material. “Draw red surface with same shader” is another one. WHAT to render – is a separate question. We don’t have much to store in this class yet, but we will later.<\/p>\n\n\n\n 5. Under xEngine <\/em>add new header (.h) file Material.h<\/strong><\/p>\n\n\n\n Location – C:\\CPP\\engine<\/em><\/p>\n\n\n\n Code:<\/p>\n\n\n <\/p>\n\n\n\n 6. Under xEngine <\/em>add new C++ (.cpp) file Material.cpp<\/strong><\/p>\n\n\n\n Location – C:\\CPP\\engine<\/em><\/p>\n\n\n\n We can leave it empty so far.<\/p>\n\n\n\n Now we are ready for our engine’s key class, which will represent WHAT to render. Also it will have Material <\/em>info, so it will know WHAT to render and HOW. I will call it a DrawJob<\/strong>.<\/p>\n\n\n\n Each game subject can have 1 or a few DrawJobs<\/em>. For example, let’s say we want to draw a red cube with a picture on 1 side. So, the subject will have 2 DrawJobs<\/em>:<\/p>\n\n\n\n TheGame <\/em>class will scan game subjects and their DrawJobs <\/em>and will execute them.<\/p>\n\n\n\n Each DrawJob <\/em>must have a reference to involved data sources, in our sample – a single vertex_buffer VBO (Vertex Buffer Object which was generated from vertices array). Each element of this VBO consists of 5 floats (alternatively it could be two arrays\/VBOs: one keeping xyz info and another one – tUV).<\/p>\n\n\n\n Also, DrawJob <\/em>must include instructions how to interpret these data: for each involved variable (such as aPos or aTuv) it must tell where it is located (in which VBO and a position\/offset inside of this VBO). So, we’ll need an extra structure, we’ll call it AttribRef <\/em>(for Attribute Reference).<\/p>\n\n\n\n VBOs themselves will reside separately (in GPU). In the DrawJob <\/em>(in AttribRefs <\/em>to be more accurate) we’ll need only VBO ids.<\/p>\n\n\n\n DrawJob class<\/strong><\/p>\n\n\n\n 7. Under xEngine <\/em>add new header (.h) file DrawJob.h<\/strong><\/p>\n\n\n\n Location – C:\\CPP\\engine<\/em><\/p>\n\n\n\n Code:<\/p>\n\n\n <\/p>\n\n\n\n 8. Under xEngine <\/em>add new C++ (.cpp) file DrawJob.cpp<\/strong><\/p>\n\n\n\n Location – C:\\CPP\\engine<\/em><\/p>\n\n\n\n Code:<\/p>\n\n\n <\/p>\n\n\n\n Try to pay a bit closer attention to this class, especially to AttribRef <\/em>structure and to it’s usage. If it’s too difficult now, don’t worry, you can come back to this later.<\/p>\n\n\n\n 9. Open TheGame.cpp<\/em> and replace code by:<\/p>\n\n\n <\/p>\n\n\n\n 10. Build and run – good.<\/p>\n\n\n\n Now let’s try on<\/p>\n\n\n\n 11. Re-start VS. Open C:\\CPP\\a998engine\\p_android\\p_android.sln<\/em>.<\/p>\n\n\n\n 12. Under xEndine <\/em>add Existing Item<\/p>\n\n\n\n Go to C:\\CPP\\engine<\/em><\/p>\n\n\n\n Pick<\/p>\n\n\n\n Add<\/strong>.<\/p>\n\n\n\n Add Android’s myUint32\/8<\/em> implementations.<\/p>\n\n\n\n 13. Open platform.h<\/em> and replace code by:<\/p>\n\n\n <\/p>\n\n\n\n 14. Switch on, unlock <\/strong>and plug in Android, allow debugging.<\/p>\n\n\n\n Build and run – perfect.<\/p>\n\n\n\n <\/p>\n","protected":false},"excerpt":{"rendered":" Windows 1. Start VS. Open C:\\CPP\\a998engine\\p_windows\\p_windows.sln MyColor class The reason to have it as a separate class, is that we will need to keep colors in THREE different formats: as an array of 4 single byte integers (from 0 to 255, as it is stored in files) as an array of 4 floats (from 0.0 to […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[4],"tags":[],"class_list":["post-497","post","type-post","status-publish","format-standard","hentry","category-cross-platform-3d"],"_links":{"self":[{"href":"https:\/\/writingagame.com\/index.php\/wp-json\/wp\/v2\/posts\/497","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/writingagame.com\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/writingagame.com\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/writingagame.com\/index.php\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/writingagame.com\/index.php\/wp-json\/wp\/v2\/comments?post=497"}],"version-history":[{"count":19,"href":"https:\/\/writingagame.com\/index.php\/wp-json\/wp\/v2\/posts\/497\/revisions"}],"predecessor-version":[{"id":1248,"href":"https:\/\/writingagame.com\/index.php\/wp-json\/wp\/v2\/posts\/497\/revisions\/1248"}],"wp:attachment":[{"href":"https:\/\/writingagame.com\/index.php\/wp-json\/wp\/v2\/media?parent=497"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/writingagame.com\/index.php\/wp-json\/wp\/v2\/categories?post=497"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/writingagame.com\/index.php\/wp-json\/wp\/v2\/tags?post=497"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}
\n\n\n\n\n#pragma once\n#include "platform.h"\n\nclass MyColor\n{\nprivate:\n float rgba[4] = { 0,0,0,0 };\n union {\n myUint32 uint32value = 0;\n myUint8 channel[4]; \/\/4 channels\n } RGBA;\npublic:\n float* forGL() { return rgba; };\n static void cloneIntToFloat(MyColor* pCl);\n static void cloneFloatToInt(MyColor* pCl);\n void setRGBA(float* rgba) { return setRGBA(this, rgba); };\n static void setRGBA(MyColor* pCl, float* rgba);\n void setRGBA(float r, float g, float b, float a) { return setRGBA(this, r, g, b, a); };\n static void setRGBA(MyColor* pCl, float r, float g, float b, float a);\n void setRGBA(int R, int G, int B, int A) { return setRGBA(this, R, G, B, A); };\n static void setRGBA(MyColor* pCl, int R, int G, int B, int A);\n void setRGBA(unsigned char* RGBA) { return setRGBA(this, RGBA); };\n static void setRGBA(MyColor* pCl, unsigned char* RGBA);\n void setUint32(unsigned int RGBA) { return setUint32(this, RGBA); };\n static void setUint32(MyColor* pCl, unsigned int RGBA);\n bool isZero() { return (RGBA.uint32value == 0); };\n bool isSet() { return (RGBA.uint32value != 0); };\n void clear() { setUint32(0); };\n unsigned int getUint32() { return (unsigned int)RGBA.uint32value; };\n};\n\n<\/pre><\/div>\n\n\n
\n\n\n\n\n#pragma once\n#include <glad\/glad.h>\n#include <stdio.h>\n\ntypedef unsigned _int64 myUint64;\ntypedef unsigned _int32 myUint32;\ntypedef unsigned _int16 myUint16;\ntypedef unsigned _int8 myUint8;\n\nvoid mylog(const char* _Format, ...);\nvoid mySwapBuffers();\nvoid myPollEvents();\nint myFopen_s(FILE** pFile, const char* filePath, const char* mode);\n\n<\/pre><\/div>\n\n\n
\n\n\n\n\n#include "MyColor.h"\n\nfloat chanIntToFloat = 1.0f \/ 255;\n\nvoid MyColor::cloneIntToFloat(MyColor* pCl) {\n\tfor (int i = 0; i < 4; i++)\n\t\tpCl->rgba[i] = chanIntToFloat * pCl->RGBA.channel[i];\n}\nvoid MyColor::cloneFloatToInt(MyColor* pCl) {\n\tfor (int i = 0; i < 4; i++)\n\t\tpCl->RGBA.channel[i] = (int)(pCl->rgba[i] * 255);\n}\nvoid MyColor::setRGBA(MyColor* pCl, float* rgba) {\n\tfor (int i = 0; i < 4; i++)\n\t\tpCl->rgba[i] = rgba[i];\n\tcloneFloatToInt(pCl);\n}\nvoid MyColor::setRGBA(MyColor* pCl, float r, float g, float b, float a) {\n\tpCl->rgba[0] = r;\n\tpCl->rgba[1] = g;\n\tpCl->rgba[2] = b;\n\tpCl->rgba[3] = a;\n\tcloneFloatToInt(pCl);\n}\nvoid MyColor::setRGBA(MyColor* pCl, int R, int G, int B, int A) {\n\tpCl->RGBA.channel[0] = R;\n\tpCl->RGBA.channel[1] = G;\n\tpCl->RGBA.channel[2] = B;\n\tpCl->RGBA.channel[3] = A;\n\tcloneIntToFloat(pCl);\n}\nvoid MyColor::setRGBA(MyColor* pCl, unsigned char* RGBA) {\n\tfor (int i = 0; i < 4; i++)\n\t\tpCl->RGBA.channel[i] = RGBA[i];\n\tcloneIntToFloat(pCl);\n}\nvoid MyColor::setUint32(MyColor* pCl, unsigned int RGBA) {\n\tpCl->RGBA.uint32value = RGBA;\n\tcloneIntToFloat(pCl);\n}\n\n<\/pre><\/div>\n\n\n
\n\n\n\n\n#pragma once\n#include "MyColor.h"\n\nclass Material\n{\npublic:\n\tint shaderN = -1;\n\tint primitiveType = GL_TRIANGLES;\n\tMyColor uColor;\n\tint uTex0 = -1;\n};\n\n<\/pre><\/div>\n\n\n
\n\n\n\n
\n\n\n\n
\n\n\n\n\n#pragma once\n#include "Material.h"\n#include <vector>\n\nstruct AttribRef \/\/attribute reference\/description\n{\n\tunsigned int glVBOid = 0; \/\/buffer object id\n\tint offset = 0; \/\/variable's offset inside of VBO's element\n\tint stride = 0; \/\/Buffer's element size in bytes\n};\n\nclass DrawJob\n{\npublic:\n\tMaterial mt;\n\tint pointsN = 0; \/\/N of points to draw\n\tunsigned int glVAOid = 0; \/\/will hold data stream attributes mapping\/positions\n\n\t\/\/common attributes\n\tAttribRef aPos;\n\tAttribRef aTuv;\n\n\t\/\/static arrays (vectors) of all loaded DrawJobs, VBO ids\n\tstatic std::vector<DrawJob*> drawJobs;\n\tstatic std::vector<unsigned int> buffersIds;\npublic:\n\tDrawJob();\n\tvirtual ~DrawJob(); \/\/destructor\n\tstatic int cleanUp();\n\tstatic int newBufferId();\n\tint buildVAO() { return buildVAOforShader(this, mt.shaderN); };\n\tstatic int buildVAOforShader(DrawJob* pDJ, int shaderN);\n\tstatic int attachAttribute(int varLocationInShader, int attributeSizeInFloats, AttribRef* pAttribRef);\n\n\tvirtual int setDesirableOffsets(int* pStride, int shaderN) { return setDesirableOffsetsBasic(this, pStride, shaderN); };\n\tstatic int setDesirableOffsetsBasic(DrawJob* pDJ, int* pStride, int shaderN);\n\n\tint execute(float* uMVP, Material* pMt) { return executeDrawJob(this, uMVP, pMt); };\n\tstatic int executeDrawJob(DrawJob* pDJ, float* uMVP, Material* pMt);\n};\n\n<\/pre><\/div>\n\n\n
\n\n\n\n\n#include "DrawJob.h"\n#include "platform.h"\n#include "utils.h"\n#include "Shader.h"\n#include "Texture.h"\n\n\/\/static arrays (vectors) of all loaded DrawJobs, VBO ids\nstd::vector<DrawJob*> DrawJob::drawJobs;\nstd::vector<unsigned int> DrawJob::buffersIds;\n\nDrawJob::DrawJob() {\n\tdrawJobs.push_back(this);\n}\nDrawJob::~DrawJob() {\n\tglBindBuffer(GL_ARRAY_BUFFER, 0);\n\tglBindBuffer(GL_ELEMENT_ARRAY_BUFFER, 0);\n\tif (glVAOid > 0)\n\t\tglDeleteVertexArrays(1, &glVAOid);\n}\nint DrawJob::newBufferId() {\n\tunsigned int bufferId;\n\tglGenBuffers(1, &bufferId);\n\tbuffersIds.push_back(bufferId);\n\treturn (int)bufferId;\n}\n\nint DrawJob::setDesirableOffsetsBasic(DrawJob* pDJ, int* pStride, int shaderN) {\n\t\/\/sets desirable offsets and stride according to given shader needs\n\t\/\/assuming that we have 1 single VBO\n\tShader* pSh = Shader::shaders.at(shaderN);\n\tint stride = 0;\n\tpDJ->aPos.offset = 0; \/\/attribute o_aPos, always 0\n\tstride += sizeof(float) * 3; \/\/aPos size - 3 floats (x,y,z)\n\tif (pSh->l_aTuv >= 0) { \/\/attribute TUV (texture coordinates)\n\t\tpDJ->aTuv.offset = stride; \/\/attribute TUV (texture coordinates)\n\t\tstride += sizeof(float) * 2;\n\t}\n\t*pStride = stride;\n\treturn 1;\n}\nunsigned int activeVBOid;\nint DrawJob::buildVAOforShader(DrawJob* pDJ, int shaderN) {\n\t\/\/delete VAO if exists already\n\tif (pDJ->glVAOid > 0) {\n\t\tglBindBuffer(GL_ARRAY_BUFFER, 0);\n\t\tglDeleteVertexArrays(1, &(pDJ->glVAOid));\n\t}\n\tglGenVertexArrays(1, &pDJ->glVAOid);\n\tglBindVertexArray(pDJ->glVAOid);\n\n\t\/\/open shader descriptor to access variables locations\n\tShader* pShader = Shader::shaders.at(pDJ->mt.shaderN);\n\n\tactiveVBOid = 0;\n\tattachAttribute(pShader->l_aPos, 3, &pDJ->aPos);\n\tattachAttribute(pShader->l_aTuv, 2, &pDJ->aTuv);\n\treturn 1;\n}\n\nint DrawJob::attachAttribute(int varLocationInShader, int attributeSizeInFloats, AttribRef* pAR) {\n\tif (varLocationInShader < 0)\n\t\treturn 0; \/\/not used in this shader\n\tif (pAR->glVBOid == 0) {\n\t\tmylog("ERROR in DrawJob::attachAttribute, nk such attribute\/VBO\\n");\n\t\treturn -1;\n\t}\n\tglEnableVertexAttribArray(varLocationInShader);\n\tif (activeVBOid != pAR->glVBOid) {\n\t\tactiveVBOid = pAR->glVBOid;\n\t\t\/\/attach input stream data\n\t\tglBindBuffer(GL_ARRAY_BUFFER, activeVBOid);\n\t}\n\tglVertexAttribPointer(varLocationInShader, attributeSizeInFloats, GL_FLOAT, GL_FALSE, pAR->stride, (void*)(long)pAR->offset);\n\treturn 1;\n}\nint DrawJob::executeDrawJob(DrawJob* pDJ, float* uMVP, Material* pMt) {\n\tif (pMt == NULL)\n\t\tpMt = &(pDJ->mt);\n\tglBindVertexArray(pDJ->glVAOid);\n\tShader* pShader = Shader::shaders.at(pMt->shaderN);\n\tglUseProgram(pShader->GLid);\n\tglUniformMatrix4fv(pShader->l_uMVP, 1, GL_FALSE, (const GLfloat*)uMVP);\n\n\t\/\/attach textures\n\tif (pShader->l_uTex0 >= 0) {\n\t\tint textureId = Texture::getGLid(pMt->uTex0);\n\t\t\/\/pass textureId to shader program\n\t\tglActiveTexture(GL_TEXTURE0); \/\/ activate the texture unit first before binding texture\n\t\tglBindTexture(GL_TEXTURE_2D, textureId);\n\t\t\/\/ Tell the texture uniform sampler to use this texture in the shader by binding to texture unit 0. \n\t\tglUniform1i(pShader->l_uTex0, 0);\n\t}\n\t\/\/other uniforms\n\tif (pShader->l_uColor >= 0) {\n\t\t\/\/float uColor[4] = { 1.f, 0.f, 1.f, 1.f }; \/\/R,G,B, alpha\n\t\tglUniform4fv(pShader->l_uColor, 1, pMt->uColor.forGL());\n\t}\n\tglDrawArrays(pMt->primitiveType, 0, pDJ->pointsN);\n\treturn 1;\n}\nint DrawJob::cleanUp() {\n\tint itemsN = drawJobs.size();\n\t\/\/delete all drawJobs\n\tfor (int i = 0; i < itemsN; i++) {\n\t\tDrawJob* pDJ = drawJobs.at(i);\n\t\tdelete pDJ;\n\t}\n\tdrawJobs.clear();\n\t\/\/delete Buffers\n\titemsN = buffersIds.size();\n\t\/\/delete all buffers\n\tfor (int i = 0; i < itemsN; i++) {\n\t\tunsigned int id = buffersIds.at(i);\n\t\tglDeleteBuffers(1, &id);\n\t}\n\tbuffersIds.clear();\n\n\treturn 1;\n}\n\n<\/pre><\/div>\n\n\n
\n\n\n\n\n#include "TheGame.h"\n#include "platform.h"\n#include "linmath.h"\n#include "Texture.h"\n#include "Shader.h"\n#include "DrawJob.h"\n\nextern std::string filesRoot;\n\nstatic const struct\n{\n float x, y, z, tu, tv;\n} vertices[4] =\n{\n { -0.5f, 0.5f, 0.f, 0.f, 0.f }, \/\/top-left\n { -0.5f, -0.5f, 0.f, 0.f, 1.f }, \/\/bottom-left\n { 0.5f, 0.5f, 0.f, 1.f, 0.f }, \/\/top-right\n { 0.5f, -0.5f, 0.f, 1.f, 1.f } \/\/bottom-right\n};\n\nDrawJob* pDJ;\nfloat angle_z = 0;\n\nint TheGame::getReady() {\n bExitGame = false;\n Shader::loadShaders();\n\n pDJ = new DrawJob();\n \/\/define material\n pDJ->mt.shaderN = Shader::spN_flat_tex; \n pDJ->mt.primitiveType = GL_TRIANGLE_STRIP;\n pDJ->mt.uTex0 = Texture::loadTexture(filesRoot + "\/dt\/sample_img.png");\n \/\/pDJ->mt.color0.setRGBA(1.f, 0.f, 1.f, 1.f);\n \/\/pDJ->mt.color0.setRGBA(255, 0, 255,255);\n\n \/\/build and attach data source(s)\n pDJ->pointsN = 4; \/\/number of vertices\n unsigned int glVBOid = pDJ->newBufferId();\n glBindBuffer(GL_ARRAY_BUFFER, glVBOid);\n glBufferData(GL_ARRAY_BUFFER, sizeof(vertices), vertices, GL_STATIC_DRAW);\n \/\/describe data source\n int stride = sizeof(float) * 5;\n \/\/attributes references\n AttribRef* pAR;\n pAR = &pDJ->aPos; pAR->offset = 0; pAR->glVBOid = glVBOid; pAR->stride = stride;\n pAR = &pDJ->aTuv; pAR->offset = sizeof(float) * 3; pAR->glVBOid = glVBOid; pAR->stride = stride;\n\n \/\/create and fill vertex attributes array (VAO)\n pDJ->buildVAO();\n \/\/end of data stream setting, now it is stored in VAO\n return 1;\n}\nint TheGame::drawFrame() {\n myPollEvents();\n\n mat4x4 m, p, mvp;\n \/\/glClearColor(0.0, 0.0, 0.5, 1.0);\n glClear(GL_COLOR_BUFFER_BIT);\n angle_z += 0.01f;\n mat4x4_identity(m);\n mat4x4_rotate_Z(m, m, angle_z);\n mat4x4_scale_aniso(m, m, 2.0, 1.0, 1.0);\n mat4x4_ortho(p, -screenRatio, screenRatio, -1.f, 1.f, 1.f, -1.f);\n mat4x4_mul(mvp, p, m);\n\n pDJ->execute((float*)mvp, NULL);\n mySwapBuffers();\n return 1;\n}\nint TheGame::cleanUp() {\n Texture::cleanUp();\n Shader::cleanUp();\n DrawJob::cleanUp();\n return 1;\n}\nint TheGame::onScreenResize(int width, int height) {\n if (screenSize[0] == width && screenSize[1] == height)\n return 0;\n screenSize[0] = width;\n screenSize[1] = height;\n screenRatio = (float)width \/ (float)height;\n glViewport(0, 0, width, height);\n mylog(" screen size %d x %d\\n", width, height);\n return 1;\n}\nint TheGame::run() {\n getReady();\n while (!bExitGame) {\n drawFrame();\n }\n cleanUp();\n return 1;\n}\n\n<\/pre><\/div>\n\n\n
\n\n\n\n
\n\n\n\nAndroid<\/h2>\n\n\n\n
\n\n\n\n
\n\n\n\n\n#pragma once\n\ntypedef uint32_t myUint64;\ntypedef uint32_t myUint32;\ntypedef uint8_t myUint16;\ntypedef uint8_t myUint8;\n\nvoid mylog(const char* _Format, ...);\nvoid mySwapBuffers();\nvoid myPollEvents();\nint myFopen_s(FILE** pFile, const char* filePath, const char* mode);\n\n<\/pre><\/div>\n\n\n
\n\n\n\n
\n\n\n\n